bluuebunny/crossref_metadata_2025 huggingface dataset:
The ecology of sublittoral communities at Abereiddy Quarry, Pembrokeshire
Authors: Hiscock K. , Hoare R.
Published: May 2009

Abereiddy Quarry is shown in Plate I. It lies at 51° 56′N, 5°13′W (Ordnance Survey Reference SM 795315), 6 km northeast of St Davids in Pembrokeshire (Text fig. 1). The quarry, a disused slate working, is surrounded by high cliffs except to the west where there is a channel open to the sea. In 1902–3, operations ceased and the quarry began to fill with fresh water and sea spray. During 1932–3 the west wall was breached to allow access to the sea so that the basin could be used as a harbour. Abereiddy is now a deep, fully saline marine basin which, at low water, is 66 m across from north to south with a surface area of 0.356 ha and a maximum depth of 24 m. In this situation it has been possible to observe sublittoral rocky sea-bed communities in an extremely sheltered area through a summer thermocline and associated oxycline. Abereiddy Quarry has previously been investigated by Bailey, Nelson-Smith & Knight-Jones (1967), who published details of the vertical distribution ofSpirorbisspp. The biology of serpulid worms in Abereiddy Quarry has been the subject of continuing investigations carried out from University College Swansea (E. W. Knight-Jones, personal communication).
The hydroids Clava multicornis and Clava squamata
Authors: Edwards C. , Harvey S. M.
Published: May 2009

There is much variation in the form of colony assumed by the common hydroid Clava, and two forms were for long distinguished as separate species, a diffuse one found on stones and rocks in the lower part of the tidal zone and in shallow subtidal depths, with scattered polyps arising from an open hydrorhizal network of creeping stolons, and a clustered one, living on fucoid and other seaweeds in the tidal zone, with densely clustered polyps borne on a compact hydrorhizal base of very short anastomosing stolons. Johnston (1847) did not separate these forms and recognized one species only, named by priority Clava multicornis (Forskal, 1775). It was largely on the authoritative works of Hincks (1868) and Allman (1871–2) that the two forms became accepted as distinct species, the name Clava multicornis (Forskål) being adopted for the diffuse one (though Hincks admitted uncertainty in ascribing Forskål name to this) and Clava squamata (Müller, 1776) for the clustered one. More recently certain authors have considered them to be forms of one species, designated by priority Clava multicornis, but others have continued to treat them as separate species, and the question of their specific identity or distinctness cannot be said to have been resolved. Broch (1916, pp. 38–40), from a study of material from various localities, concluded that there are all transitional conditions between the two forms, rendering specific distinction impossible, and that they are evidently ecologically conditioned forms of one species. He did not, however, adduce any experimental or other evidence in support of his belief.
On the northern rockling Ciliata septentrionalis (Collett) in the Plymouth area
Authors: Dando P. R.
Published: May 2009

The known range of the northern rockling, Ciliata septentrionalis, extends from Iceland and northern Norway in the north to Plymouth in the south (Wheeler, 1965). This species has probably been confused with the five-bearded rockling, C. mustela (L.), in the past (Wheeler, 1969) and this together with the small size of the fish, enabling it to escape through the mesh of most trawls, may explain the paucity of records and knowledge of the species. Brook, (1885, 1888) described the egg and larval development of C. mustela but the egg and larva of C. septentrionalis have not been described. It is probable that the abundance of both these species can only be estimated by a combination of fecundity studies and egg and larval counts.
The advance and retreat of the thermocline on the continental shelf
Authors: Pingree R. D.
Published: May 2009

An important factor in the seasonal cycle of phytoplankton growth is the establishment and breakdown of the seasonal thermocline (Sverdrup, Johnson & Fleming, 1946). When surface heating is sufficient, more buoyancy is produced than can be dissipated by wind and tide. The stabilization of the water column allows the phytoplankton sufficient time in the surface layer to utilize the light energy for increased net production and the spring bloom is triggered. At the end of the summer period the erosion of the thermocline may result in an increase of nutrients in the upper layers. If production has become limited by surface depletion of nutrients during the summer, then the thermocline breakdown may result in an autumnal bloom particularly if a period of calm sunny weather follows. The importance of the thermocline development and season length is clearly illustrated in plankton studies of the North Atlantic, for example Robinson (1970).
A time-varying temperature model of mixing in the English Channel
Authors: Pingree R. D. , Pennycuick Linda , Battin G. A. W.
Published: May 2009

The most comprehensive hydrographic work on the English Channel, even today, is that of Lumby (1935). Lumby used the surface observations of ships of opportunity (steamers on regular routes) that were gathered over a period of 25 years from 1903 to 1927. The number of observations gathered runs into tens of thousands and these were subdivided into convenient regions for the purpose of constructing an Atlas of sea surface temperature and salinity. The mean monthly values of temperature for each region from which the monthly contours were drawn can be considered as established to within ± 0.2 °C. Despite the fact that these data have been available for half a century no satisfactory explanation for these monthly temperature distributions has been offered. In this paper the role of horizontal turbulence in redistributing the net surface heating to produce these monthly temperature distributions is quantitatively examined.
The Swimming Rhythm ofBathyporeia Pilosa[Crustacea: Amphipoda]
Authors: Preece G. S.
Published: May 2009

High- and low-shore populations ofBathyporeia pilosaLindstrÖm, kept in the laboratory under natural day-night illumination and constant dark conditions, show distinct swimming rhythms of tidal frequency (12–4 h) with activity maxima on the early ebb tide. A diurnal component is evident, activity during thenight being greater than during the day. The tidal rhythm deteriorates under laboratory conditions, but swimming activity recurs after a semi-lunar period. Under natural illumination, both populations show a night tide swimming rhythm of semi-lunar frequency, activity occurring mainly over the 'falling' spring tides. Plankton sampling on night tides over the area of the beach occupied by high-shoreB. pilosashows that the animals emerge and swim on ebb tides which are in phase with darkness. The importance of exogenous factors such as wave action, pressure, temperature and light is discussed. Ecological implications and the possible function of the swimming rhythm are considered.
Liberation of Extracellular Products of Photosynthesis by Tropical Phytoplankton
Authors: Samuel S. , Shah N. M. , Fogg G. E.
Published: May 2009

Using14C as a tracer in experiments of 2–3 h duration it has been demonstrated, both with individual species in culture and natural populations, that marine phytoplankton from tropical inshore waters releases products of photosynthesis insoluble extracellular form. The relative extent of this excretion varied between 1% and 20% of the total carbon fixed but on any particular occasion the amount of extracellular products was approximately proportional to the amount ofphotosynthesis which had taken place. An inverse relation-ship between relative extent of excretion and phytoplankton abundance as measured by chlorophyllα concentration was found, in agreement with the results of previous workers. The relative extent of excretion did not appear to be greatly different in brackish water of 12–3% salinity from that in ordinary sea water.
Temperature Acclimation of Mytilus Edulis With Reference to its Energy Budget
Authors: Widdows J. , Bayne B. L.
Published: May 2009

Mytilus edulis L. is shown to acclimate to high and low temperature under laboratory conditions. The warm and cold acclimation of oxygen consumption, filtration rate and assimilation efficiency are described for groups of animals maintained at three food-cell concentrations. Complete acclimation (Precht's type 2) of oxygen consumption and filtration rate occur within 14 days. There is no change in assimilation efficiency within the 28-day experimental period. The results are integrated and discussed in the context of a simple energy budget. In terms of the energy budget there exists a marked contrast between warm and cold acclimation. An “index of energy balance” is proposed in order to assess the state of the energy balance. When animals are fed above the maintenance requirement the energy budget remains in an equilibrium state during cold acclimation, whereas the acclimation to a warm temperature regime disrupts the balance and represents a physiological stress. During warm acclimation, prior to the re-establishment of an energy equilibrium the blood sugar level increases, suggesting that the animal is required to mobilize and utilize its energy reserves.
Adaptation of the polychaeteNereis diversicolorto estuarine sediments containing high concentrations of heavy metals. I. General observations and adaptation to copper
Authors: Bryan G. W. , HummerstonE L. G.
Published: May 2009

The concentration of copper inNereis diversicolorO. F. Miiller is roughly related to the total concentration in the sediment and particularly high concentrations are found where mining pollution occurs. In contrast, the concentration ofzinc inNereisremains remarkably constant despite wide variations in the environment and appears to be accurately regulated.
The Distribution Of Visual Pigment Within The Retina In Two Teleosts
Authors: Denton E. J. , Muntz W. R. A. , Northmore D. P. M.
Published: May 2009

The distribution of the visual pigments within the retina of the rudd, Scardinius erythrophthalmus, and dragonet, Callionymus lyra L., was studied by measuring the spectral absorbance of small areas of intact isolated retinas.

The rudd retina contains two visual pigments, VP 5O71 and VP5352. There is a progressive change in the relative proportion of these two pigments in the dorso-ventral plane, and there are no sharply defined zones each with a different pigment mixture. The proportion of the A1-based pigment (VP 5071) is greater in the dorsal part of the retina.

The maximal optical density of the pigment in the dorsal retina of the rudd was greater (about o·6) than it was in the ventral retina (about 0·3). The difference in the amount of light absorbed, however, is small compared to the intensity difference between the up-welling and downwelling light of the environment. When the relative proportion of the A1- and A2-based pigments was changed by altering the lighting conditions under which the animals were kept there was little or no change in the maximal optical density of the pigment.

In the dragonet the retina shows a clear division into a ventral pink zone (maximal optical density about 0·5) and a dorsal zone that is much paler (maximal optical density about 0·2). The relative spectral absorbance of the two regions is similar, although one is said to be a pure cone region, and the other to be dominated by rods.

The spectral absorbance curves for the intact retinas agreed well with results obtained with pigment extracts.
Biochemical Studies on Marine Zooplankton X.The Amino Acid Composition ofEuphausia Superb a, Meganyctiphanes NorvegicaandNeomysis Integer
Authors: Srinivasagam R. T. , Raymont J. E. G. , Moodie C. F. , Raymont J. K. B.
Published: May 2009

The amino acid composition has been investigated in two euphausiids,Euphausia superbaDana andMeganyctiphanes norvegica(M. Sars), and one mysid,Neomysis integerLeach. Protein-bound amino acids show a very considerable degree of similarity: glutamic acid, aspartic acid, lysine, leucine and arginine are predominant in all three crustaceans, and occur in that order of importance. Together they amount to ~ 50% of the total protein hydrolysates. Concentrations of free amino acids show greater differences between the zooplankton species, but taurine, glycine and arginine are very important in all three. Lysine and ornithine occur in fair quantities in both euphausiids, and proline and alanine are moderately important inEuphausia superbaandNeomysis integer.
Observations on the Fine Structure of Zoids of the GenusPhaeocystis[Haptophyceae]
Authors: Parke M. , Green J. C. , Manton I.
Published: May 2009

Observations on the fine structure of two clones of zoids derived fromPhaeocystis pouchetiis.l. are presented, with special reference to the scales, pyrenoids and haptonema, in which both clones agree. An unexplained difference between them in the form of a threadlike deposit external to the scales in one clone only is described in a preliminary way. The most remarkable feature encountered is the presence of some unexplained bulbous inclusions distorting the tip of the haptonema but perhaps also present in a less extreme form in other types recently examined alive. The interpretation of these findings is discussed.
The Assimilation of Nutrients from Compounded Diets by the PrawnsPalaemon SerratusandPandalus Platyceros
Authors: Forster J. R. M. , Gabbott P. A.
Published: May 2009

Assimilation efficiency (percentage of nutrients absorbed) from diets compounded from dry food meals was investigated using the prawnsPalaemon serratusPennant andPandalus platycerosBrandt. An indirect ratio method using chromic oxide (Cr2O3) as an inert reference material in the diet was employed, but the method was complicated by the prawns' habit of regurgitating part of the indigestible food remains after a meal. Thus quantitative collection of both faeces and the regurgitated, unassimilated food fraction was necessary.
The Uptake of Radionuclides by I-Group Plaice (Pleuronectes Platessa) off the Cumberland Coast, Irish Sea
Authors: Pentreath R. J. , Jefferies D. F.
Published: May 2009

The accumulation of radionuclides by I-group plaice, Pleuronectes platessa L., in the vicinity of the pipe-line of the UKAEA plant at Windscale, Irish Sea, has been studied over a 7–month period. The principal isotope found in the flesh was 137Cs, although 144Ce, 106Ru, and 95Zr/95Nb were also present in the gut contents. The 137Cs flesh levels were examined in conjunction with the fluctuations of this nuclide in sea water, sediment and the gut contents. Of the three major dietary components found throughout the sampling period the calculated intake of 137Cs from food appeared to fluctuate most closely with the Nephtys fraction of the diet, despite its relatively low 137Cs content.
New Observations on the Lymph System of the PlaicePleuronectes Platessaand other Teleosts
Authors: Wardle C. S.
Published: May 2009

The anatomy of the teleost lymph system is considered in relation to the observed flow of lymph. The plaicePleuronectes platessaL. was studied.

The vessels described by anatomists as longitudinal ventral, dorsal and lateral lymph ducts do not pass lymph to the head but act as collecting sinuses; the lymph flows from these sinuses to the neural lymph duct via the interspinal ducts.

At the junction of each interspinal duct and the neural lymph duct there is a simple valve. Lymph drains through this system as a result of a negative pressure developed in the neural canal by the respiratory movements of the gill apparatus.

The rigid nature of the neural lymph duct and the valves where the interspinal ducts join it allow the negative pressure to develop from a negative positive gill generated pres-sure cycle in the cephalic lymph sinuses. Valves Unking cephalic lymph sinuses aid the return of lymph to the duct of Cuvier using the same pressure cycles.

The drainage system is different in the salmonidae where the neural lymph duct is degenerate and the network of peripheral ducts serve as lymph return ducts. This can probably be explained by the occurrence of higher circulation pressures in the salmonidae.

Lymph from the neural lymph duct is a clear fluid having a composition similar to that of blood plasma. Like blood, lymph clots, and contains normal blood levels of mobile leucocytes and thrombocytes and lymph reflects blood levels of lactate. Lymph contains nearly no erythrocytes and the protein concentration of neural duct lymph is 80–4% that of blood plasma.
Professor J. S. Alexandrowicz
Authors: Bone Q.
Published: May 2009

Prof. Jerzy Stanislaw Alexandrowicz, who died at Plymouth on 28 October 1970, was one of the most distinguished histologists of the nervous system, whose series of memoirs upon invertebrate peripheral nervous systems stimulated much physiological and histo-logical research. He was born at Stoczki, in Poland, on 2 August 1886, and after matriculating in Warsaw studied medicine and natural science at the universities of Warsaw, Zurich, Munich, Heidelberg, Paris and Jena. He took his Ph.D. at Zurich under Lang, and his M.D. at Jena, under Biedermann, serving for a short period as a surgeon in the Military hospital at Belgrade, before being appointed to the department of descriptive anatomy at Wilno. He remained here during the war, and in 1918 served with the field hospitals coping with epidemic diseases brought to Poland from the East. He himself survived an attack of typhus. In 1919 he was appointed to organize and direct the department of descriptive anatomy at Wilno, and the next year rejoined the army to serve as the chief medical officer of a cavalry regiment in the fighting against Russia.

In 1920 he returned to Wilno, as head of the department of histology, and remained there until 1929, when he moved to Lwow, again as director of the department of histology, in the Academy of Veterinary medicine. In 1933 he became Pro-Rector of the Academy, and in 1936 Reaor, finally leaving the university in 1937 to head the scientific and university department of the Ministry of Education. He quickly became Under-secretary of State for Education, and in 1938 relinquished this post to spend six months at the Stazione Zoologica, Naples, where he had previously worked on three occasions.
The Behavioural Basis of Predator-Prey Size Relationships Between Shrimp (Crangon Crangon) and Juvenile Plaice (Pleuronectes Platessa)
Authors: Gibson R.N. , Yin M.C. , Robb L.
Published: May 2009

The shrimp,Crangon crangon(L.) (Crustacea: Crangonidae), is a significant predator of the smallest sizes of plaice,Pleuronectes platessaL. (Teleostei: Pleuronectidae), during and immediately after the fish settle on sandy beaches when predation rate is strongly dependent on the size of both the predator and the prey. Laboratory experiments showed that this size-dependency is caused principally by the superior escape capabilities of larger fish once captured rather than differences in the ability of different sizes of shrimps to capture their prey. Fish that escape after capture are often wounded and some of these wounds may subsequently be fatal. Many shrimps capture and eat fish that are larger than their stomach volume resulting in long handling times and low prey profitabilities. For all sizes of shrimps used (36–65 mm total length) prey profitability (mg prey ingested min−1) increases with decreasing fish length.
Dynamics and Growth of a Recent Invader into European Coastal Waters: the American Razor Clam,Ensis Directus
Authors: Beukema J.J. , Dekker R.
Published: May 2009

Densities and growth rates ofEnsis directus(Bivalvia: Solenidae), a recent invader of the Wadden Sea, were monitored at 15 stations (12 transects and 3 squares) covering a wide range of intertidal levels and sediment types on Balgzand, a tidal-flat area in the western-most part of the Wadden Sea, during 1982–1994. In this period, recruitment was weak in all but one year (1991). Settlement took place in summer over a wide range of intertidal levels, but high survival of recruits was limited to stations below the level of mean low tides. Growth rates were also maximal at these low intertidal levels. In such areas they reached a mean length of about 6 cm in the first winter, about 12 cm in the second, and about 14 cm in the third winter. These growth rates were high compared with published records from other intertidal and shallow subtidal areas.

Relatively exposed parts of the lower intertidal zone, characterized by clean sands and infrequent emersion, are a poorly occupied habitat of the Wadden Sea and offer an available niche to a new species that is well adapted to such harsh environmental conditions. In such areas,E. directushas become a dominant member of the benthos and in 1992 and 1993 reached high biomass and production values of >10 g AFDW m−2.
Periostracal Adventitious Hairs on Spat of the MusselMytilus Edulis
Authors: Dixon D.R. , Cava-Sole A.M. , Pascoe P.L. , Holland P.W.H.
Published: May 2009

Morphological and genetic evidence is presented which supports the existence of periostracal adventitious hairs on spat of the musselMytilus edulis.This character appears not to have been reported previously forMytilus, and was thought to be restricted to a closely-related genus,Modiolus.The species identity of hairy mussel spat was confirmed by PCR (polymerase chain reaction) amplification of a diagnostic portion of the nuclear ribosomal DNA repeat unit (i.e. the ITS-2 region). Size-frequency analysis of spat, sampled in mid-September 1993, from rock pools and from the byssus of a nearby adult mussel bed, showed that hairy spat (mean shell length 1.87 mm, SE 0.17) were significantly (t=7.74; P<0·001) smaller than smooth-shelled spat (mean shell length 2.77 mm, SE 0.28), although not all small-sized individuals displayed this character. These findings suggest that there is a gradual loss of hairs (through abrasion or by ‘programmed’ loss) as the animal grows. We suggest that this character has some adaptive significance since it probably reduces predation by boring gastropods (e.g. juvenileNucella lapillus) and may inhibit fouling, particularly by conspecifics, during the primary settlement phase.
An Outline Of The Biology of the Squid Illex Coindetii in the Sicilian Channel (Central Mediterranean)
Authors: Jereb P. , Ragonese S.
Published: May 2009

INTRODUCTION

The genus Illex is likely to constitute a large portion of the annual world ommastrephid squid catches (Roper et al, 1984), even though specific official statistics are difficult to obtain. The broad-tail short-fin squid Illex coindetii is a widespread species ranging from the western to the eastern Atlantic (Roper et al., 1984) and east through the whole Mediterranean Sea (Mangold & Boletzky, 1987). Usually a by-catch of important fisheries, it is caught mainly by trawlers. Although its economic value is lower than that of other squid species (i.e. Loligo spp.), in the Sicilian Channel Illex coindetii may represent a valuable resource due to its abundance.

In Italian waters, the available statistics (Cingolani et al., 1986) report that 2680 tonnes of ommastrephid squid were landed in 1982 (0.5% of the total landed catch). The main component of these was landed in Sicily (2183 tonnes), a consistently large part of which was no doubt Illex coindetii (Ragonese & Jereb, 1992). The catches came mainly from southern Sicilian waters (Sicilian Channel) where one of the major Mediterranean landing places is in Mazara del Vallo. Large trawlers (up to 200 gross tonnage) usually carry out long fishing trips (15–20 d), and Illex coindetii is caught mainly by those targeting Parapenaeus longirostris and Merluccius merluccius (Jereb & Ragonese, 1991).
Inter- and Intra-Beach Thermal Variation for Green Turtle Nests on Ascension Island, South Atlantic
Authors: Hays Graeme C. , Adams Colin R. , Mortimer Jeanne A. , Speakman J.R.
Published: May 2009

Nest temperatures for green turtles (Chelonia mydas) nesting on Ascension Island, South Atlantic (7°57'S 14°22'W), were examined. Temperature probes were placed into nests on two beaches, Long Beach (26 nests) and North East Bay (8 nests). Within these beaches there was relatively little thermal variation (SD of nest temperature was 0.32°C for Long Beach and 0.30°C for North East Bay). To examine inter-beach thermal variation temperature probes were buried at 55 cm on 12 beaches. Inter-beach thermal variation was large and was related to the beach albedo with the darkest beach (albedo, 016) being 4.2°C warmer than the lightest coloured beach (albedo, 0.73).
Spatial Variation in an Algal Turf Community with Respect to Substratum Slope and Wave Height
Authors: Whorff J.S. , Whorff L.L. , Sweet M.H.
Published: May 2009

A mid-shore colonial algal turf community is described. Samples were analysed to determine if species composition, invertebrate epiphyte density, algal mat biomass, and the amount of sediment trapped among algal thalli differed with respect to substratum slope and wave height.

Colonial algal turf was approximately 1–3 cm in height and predominantly composed of a mixture of four species of eurythermal red algae, including Gelidium crinale (Turner) Lamouroux (Rhodophyceae: Gelidiales), Centroceras clavulatum (C. Agardh) Montagne, Polysiphonia denudata (Dillwyn) Kuetzing, and Bryocladia cuspidata (J. Agardh) De Toni (Rhodophyceae: Ceramiales). More delicate algae and algal epiphytes were found at stations with lower mean wave height, while non-epiphytic coralline algae were found only at stations with higher mean wave height. Algal mat mass was significantly greater on horizontal slopes than on vertical slopes, but did not differ with respect to wave-height levels. Algal mats trapped significantly more sediment on horizontal slopes with lower mean wave height.

Densities of the three most abundant invertebrate epiphytes appeared to be related to sediment deposition. Like sedimentation patterns, disparities in population densities on different substratum slopes increased with lower mean wave height. The highest densities of the amphipods Elasmopus rapax Costa and Hyale frequens Haswell (Crustacea: Peracarida) occurred on horizontal slopes at stations with significantly lower mean wave height. The highest densities of the tree oyster Isognomon bicolor C.B. Adams (Mollusca: Pterioida) were on vertical slopes at stations with significantly lower mean wave height. Barnacle epiphytes occurred in higher densities at stations receiving greater mean wave height, while dominant species of other crustaceans and molluscs had higher densities at stations with significantly lower mean wave height.
Fatty Acids of Hydrothermal VentRidgeia Piscesaeand Inshore Bivalves Containing Symbiotic Bacteria
Authors: Fullarton J. Gregor , Dando Paul R. , Sargent John R. , Southwards Alan J. , Southward Eve C.
Published: May 2009

Ridgeia piscesaefrom a hydrothermal vent and lucinid and thyasirid bivalves from inshore Canadian and UK waters, known to contain sulphur-oxidizing symbiotic bacteria, had lipids rich in 16:0,16:l(n-7) and 18:l(n-7) fatty acids in both bacteria-rich trophosome or gill tissue and in tissues without symbiotic bacteria. The results are consistent with the animals deriving these fatty acids from their sulphur-oxidizing symbionts.Ridgeia piscesae, Lucinoma annulata, Parvilucina tenuisculpta, Lucinoma borealisandMyrtea spiniferaalso contained substantial amounts of the non-methylene-interrupted dienoic fatty acids 20:2δ5,13 and 22:2δ7,15. It is proposed that these fatty acids are produced by chain elongation and δ5 desaturation in animal tissues of 18:l(n-7) produced by the bacterial symbionts.Thyasira flexuosadid not contain 20:2δ5,13 or 22:2δ7,15 but instead contained 18:l(n-ll) and 20:l(n-13) which were not present in the other species analysed. It is proposed that 18:l(n-ll) and 20:l(n-13) arise from the δ9 desaturation of 20:0 and 22:0, respectively, followed by chain shortening of the mono-unsaturated fatty acid products of δ9 desaturation. It is considered that 20:2δ5,13 and 22:2δ7,15 are formed in the animals in response to a relative excess of 16:0, 16:l(n-7) and 18:l(n-7), accompanied by a relative deficiency of (n-3) and (n-6) polyunsaturated fatty acids. The results are discussed in relation to the lipid nutrition of marine invertebrates containing bacterial symbionts.
Hectocotylus Regeneration In Wild-Caught Sepiolid Squids
Authors: Bello Giambattista
Published: May 2009

Post-traumatic regeneration of arms in Cephalopods is a common occurrence. It was described by Aristotle and, in more modern times, by Steenstrup (1856). Féral (1978) summarizes the information on regeneration of arms, tentacles and suckers in cephalopods. He reports only one case, experimental, involving a Sepiolidae species, namely Sepiola atlantica.

This paper gives an account of regeneration of the copulatory arm in three wild-caught male sepiolid squids, two of which were Sepietta oweniana (d'Orbigny, 1841) and one Sepiola ligulata Naef, 1912 (Sepiolidae: Sepiolinae). The copulatory arm, or hectocotylus, is the left dorsal arm in Sepiolinae. It represents a most important means of species identification (Naef, 1923; Bello, in press). The squids were caught by bottom trawl in the southern Adriatic Sea during routine sampling. Measurements and observations were made on preserved specimens.
Does Nidamental Gland Jelly Induce the Formation of Perivitelline Space at Fertilization in the Squid Todarodes Pacificus?
Authors: Ikeda Yuzuru , Shimazaki Kenji
Published: May 2009

Squids have more than two accessory reproductive glands, namely oviducal and nidamental glands which release gelatinous substances at the time of spawning to produce an egg mass and in some sepiolids and loliginids there also exist accessory nidamental glands (Hamabe, 1962; Boletzky, 1986; Mangold, 1987). An exception are some enoploteuthid squids which lack the nidamental glands but have large oviducal glands (Naef, 1923). Ikeda et al. (1993) showed experimentally that the gelatinous substance from the oviducal gland has the role of generating the elevation of the chorion at fertilization, which causes the formation of the perivitelline space in squid such as Todarodes pacificus; the perivitelline space became larger during embryonic development in the presence of the oviducal gland jelly. Since T. pacificus lacks accessory nidamental glands (Sasaki, 1921), we address the question as to whether the gelatinous substances of nidamental gland origin also induce the formation of perivitelline space, as does the oviducal gland jelly in T. pacificus, based on the observations of artificial insemination.
A Cyphonautes Larva (Bryozoa: Gymnolaemata) from the Bellingshausen Sea, Antarctica
Authors: Shreeve Rachael S. , Hayward Peter J.
Published: May 2009

Bryozoans are an important component of the sessile, suspension-feeding fauna on the Antarctic continental shelf, (Knox & Cameron, 1970; Dell, 1972; Winston, 1983; Winston & Heimberg, 1988). Antarctic bryozoan faunas are systematically diverse, and display a broad range of colony morphotypes; they include fast-growing, short-lived species and long-lived perennials (Winston & Heimberg, 1988). Very little is presently known about the reproductive biology of Antarctic bryozoans, although it seems that a preponderance of species brood lecithotrophic larvae with a short, free-swimming phase. Planktotrophic larvae with a free-swimming phase of several weeks occur in a variety of gymnolaemate families, principally distributed in temperate coastal waters, and most often associated with specialized microhabitats or substrates. This type of larva, referred to as a cyphonautes (Zimmer & Woollacott, 1977), has not previously been reported from polar seas, and its occurrence in the Bellingshausen Sea, Antarctica, is thus of considerable interest.
The Distribution and Ecology of the Interstitial Meiofauna of a Sandy Beach at Whitsand Bay, East Cornwall
Authors: Harris Roger P.
Published: May 2009

The interstitial meiofauna was investigated on an exposed sand beach at Whitsand Bay, Cornwall. An intertidal transect of eight stations was sampled regularly over a period of 2 years from May 1968 to May 1970. Quantitative core samples were taken to a depth of 50 cm. Nematodes were the dominant group on the beach, forming about 50% of the meiofauna. Harpacticoid copepods were second in overall abundance. Hydrozoa, turbellaria, gastrotrichs and tardigrades were also present.
The Functional Morphology and Geographical Distribution of Planktomya Henseni, a Supposed Neotenous Pelagic Bivalve1
Authors: Allen John A. , Scheltema Rudolf S.
Published: May 2009

Planktomya henseni Simroth 1896 is a pelagic bivalve widely distributed throughout the warm-temperate and tropical North and South Atlantic Ocean. It is also known from a single collection in the tropical Pacific Ocean. The geographical distribution of Planktomya is probably circumtropical.
Seasonal Variation of the Suspended Solid Matter, off the Coast of North Yorkshire
Authors: Newton Andrew J. , Gray John S.
Published: May 2009

An investigation into the natural regime of coastal suspended solids before discharge of potash mining waste is described. Regular samples of suspended material were taken over the period September 1968 to August 1970. Statistical analyses showed significant differences in suspended solid values between the months and between inshore and offshore sampling stations. There was no significant difference between sampling points along the coast. The inshore suspended solid values were low from May to September. At other months and at the offshore stations there was a gradual change from summer (low) to winter (high) values and vice versa.

Sea temperature, sea state, tidal range and river flow correlated significantly with suspended solid values. It is suggested that wave action, tidal currents and river flow control most of the variation in load of suspended matter off the N. Yorkshire coast. The significant negative correlation between temperature and suspended solid values is not regarded as a causal relationship. Low temperatures are associated with high wave activity and high river flow rates; factors which are more likely to have a causal relationship with suspended solid loads than temperature. Thus, suspended matter variations off the Yorkshire coast are probably determined by physical rather than biological temperature-dependent processes.

From multiple linear regression analyses, sea state, tidal range and river flow were found to account for 64·1% of the variation of the inshore suspended solid values and 52·4% of the variation of offshore values. Using the multiple regression equations as mathematical models it was possible to derive accurate predictions of the natural suspended solid load.
The Distribution of Marine Shell-Boring Green Algae
Authors: Wilkinson M. , Burrows E. M.
Published: May 2009

The vertical and horizontal distribution on the shore and the distribution between the host shell species, is described for a number of species of green shell-boring algae. A list is given of the records made in Britain for shell-boring Codiolum stages and for Entocladia perforans. An account is given of the sequence in which shell-boring algae attack Spirorbis worm tubes in the Isle of Man.
The Hydroids and the MedusaePodocoryne Areolata, P. Borealisand P.Carnea
Authors: Edwards C.
Published: May 2009

Three species of medusae of the genusPodocoryneM. Sars have been collected in the Clyde Sea Area:P. hartlaubiNeppi & Stiasny,P. borealis(Mayer) andP. cameaM. Sars. Their hydroids have also been found there, and medusae liberated in the laboratory have been reared to maturity. Detailed illustrated accounts of the hydroids and of the developmental stages of the medusae are given.

The hydroid ofP. hartlaubiproves to be identical with the hydroidPodocoryne areolata(Alder), a species long known to liberate medusae, which however have not previously been referred with certainty to any known species of medusa. By priority the nameP. areolatahas seniority overP. hartlaubiand applies to both hydroid and medusa. The hydroidP. hartlaubireported from Naples by Yamada is discussed, and is considered to be identical withP. areolata. In the Clyde Sea Area the hydroid has been found only on certain small gastropod shells occupied by hermit-crabs.

The hydroid ofP. borealishas hitherto been very inadequately known. The hydroid is very common in the Clyde Sea Area, living on a variety of host animals on muddy grounds. Colonies have also been reared in the laboratory from ripe medusae caught in the sea. Abundant material has accordingly been obtained, making possible a full description of the species.
Metamorphic Changes in the Velar Musculature, Head and Shell of some Prosobranch Veligers
Authors: Fretter Vera
Published: May 2009

The velum of Lacuna vincta (Montagu) and Nassarius incrassatus (Ström) is retracted into the shell by 2 dorsal and 2 ventral groups of muscles, bilaterally arranged, which are components of the larval retractor muscle. Each dorsal group passes forward from its area of origin on the shell to the dorsal part of the head where some fibres insert and adjacent ones enter the velar fold. The velum is bilobed in Lacuna and the muscles radiate through the dorsal half of the lobe to insert on the anterior and posterior surfaces and ciliated edge, whereas Nassarius has 4 long velar lobes, 2 dorsal and 2 ventral, and the muscles form a median bundle from which fibres radiate to similar insertions. Each ventral group of muscles passes through the nerve ring lateral to the developing radular sac in Lacuna and to the developing proboscis in Nassarius, and muscles accompanying them insert on the sac and proboscis wall. Anterior to the ring some muscles insert on the lips and the buccal wall posterior to the oral sphincter and alongside attachments of muscles from the foot. The majority pass to the mentum, a median protuberance of the lower lip with non-vibratile cilia, where right and left ventral cephalic retractors and muscles from the foot converge. The pedal muscles attach here and from this area muscles radiate to multiple insertions on the head and ventral half of the velum. This arrangement of the ventral muscles allows the increased angle of mobility required by the ventral areas of the velum in swimming and feeding and the intimate contact between velum and foot.
Some Observations on the Tolerance of Oceanic Plankton to High Hydrostatic Pressure
Authors: Macdonald A. G. , Gilchrist I. , Teal J. M.
Published: May 2009

The activity of the following planktonic animals has been observed at hydrostatic pressures up to 500 atm: Gigantocypris mülleri, Conchoecia hyalophyllum, C. macrocheira, C. rhynchena, Parathemisto sp., Megacalanus longicornis, Euaugaptilus magna, Pareuchaeta gracilis, Pleuromamma robusta, Anomalocera patersoni, Euphausia krohni, Acanthephyra pelagica and Amalopeus elegans. Respiration of Gigantocypris and Systellaspis debilis was also measured at pressure.
Food and Feeding Habits ofLuidia CiliarisEchinodermata: Asteroidea
Authors: Brun Einar
Published: May 2009

Luidia ciliaris(Philippi) has intraoral digestion and was found to be a selective feeder on echinoderms. In 258 specimens from the Irish Sea, echinoderms occurred in 97·4% of all stomachs containing food and contributed 92% of the food volume (estimated by points method). The most important food items werePsammechinus miliaris, Ophiothrix fragilis, Ophiura albidaandOphiocomina nigra. Ophiocomina nigradid not occur as frequently as would be expected from their availability. Observationin siturevealed that large specimens had efficient escape response to movingLuidiaand aquarium experiments showed thatO. nigradeprived of their moving ability were readily eaten. However, theLuidiashowed clear preference toOphiothrix fragilis.There was no distinct seasonal difference in the composition of the diet, but a tendency to a minimum feeding activity in May-June, probably connected with the spawning period.
The Influence of Current Speed, Body Size and Water Temperature On the Filtration Rate of Five Species of Bivalves
Authors: Walne P. R.
Published: May 2009

The rate of water filtration by bivalves has long excited interest, but it has in practice proved difficult to measure in conditions where the animal is relatively free from constraint. Its estimation is important from a number of aspects: feeding studies; as an indicator of the animal's reaction to its environment; and for predicting the flow of water required for the culture of economically important species. The work reported in this paper started as part of the general programme on shellfish culture in progress at this laboratory. During the development of a suitable method for studying the water requirements it became clear that one factor, water current, had a more important influence than has been generally recognized.
Seasonal Changes in the Meiofauna Population of an Intertidal Sand Beach
Authors: Harris Roger P.
Published: May 2009

In spite of the increasing interest in the ecology of interstitial meiofauna (Fenchel, Jansson & Thun, 1967; Gray & Rieger, 1971;Jansson, 1968; Renaud-Debyser, 1963; Renaud-Debyser & Salvat, 1963; Schmidt, 1968,1969) little is known about the seasonal changes that occur in interstitial populations. A number of seasonal studies have been made of groups within the meiofauna–for example, tardigrades (Pollock, 1970) and nematodes (Skoolmun & Gerlach, 1971). However, Schmidt (1968, 1969) provides the only information for a total meiofauna population based on regular sampling over a complete year's cycle.
Attachment of the Coral Caryophyllia Smithii S. & B. to Tubes of the Polychaete Ditrupa Arietina (Müller) and other Substrates
Authors: Wilson John B.
Published: May 2009

INTRODUCTION

Little is known about the early growth history of solitary corals in relation to the substrates to which they are attached. An understanding of this relationship between coral and substrate, and of how it may change throughout the life of the coral, is particularly important in studies of the life history and ecology of solitary corals living in sand and other soft sediments. A knowledge of the variety of different substrates to which solitary corals are attached in the wide range of different environments in which they live is also of importance to the palaeontologist when attempting palaeoecological interpretation of transported coral debris.
Feeding, Growth and Reproduction of the Marine Planktonic Copepod Pseudo-Calanus Elongatus Boeck
Authors: Paffenhöfer G.-A. , Harris R. P.
Published: May 2009

INTRODUCTION

The development of techniques to culture calanoid copepods over multiple generations in the laboratory has resulted in considerable advances in knowledge about a group of animals of major importance in the marine food web. A series of extensive studies have been made of two species of large calanoids, Calanus helgolandicus (Claus) (Mullin & Brooks, 1967, 1970a, 1970b; Paffenhöfer, 1970, 1971, 1976a, 1976b), and Rhincalanus nasutus Giesbrecht (Mullin & Brooks, 1967, 1970a, 1970b). Feeding, growth, and reproduction have been studied under controlled conditions, using different temperatures, food species, and food concentrations. Some of the information gained in these studies has been incorporated into a simulation model of the planktonic ecosystem of the North Sea (Steele, 1974). However, in the North Sea and in many other sea areas species of small copepod probably form an important component of the food web. Little information is available on the quantitative biology of these small copepods under controlled conditions.
The Vertical Distribution and Diurnal Migration of the Crustacea Amphipoda Collected During the SOND Cruise, 1965 I. The Gammaridea
Authors: Thurston Michae L H.
Published: May 2009

INTRODUCTION

Detailed studies of the vertical distribution and migration of the micronekton, plankton and sonic scattering layers in an oceanic environment off Fuertaventura in the Canary Islands were made from R.R.S. ‘Discovery’ during September to December 1965. A general account, including a statement of the objectives of the cruise, has been given by Currie, Boden & Kampa (1969). Foxton (1969) has described the biological sampling methods and techniques utilized. Results of sonic scattering investigations have been published by Blaxter & Currie (1967) and Boden & Kampa (1967). The present study deals only with the pelagic amphipods, and forms a contribution to a series (Angel, 1969; Clarke, 1969b; Baker, 1970; Foxton, 1970a, b; Badcock, 1970; Roe, 1972a, b, c, d; Pugh, 1974) dealing with the distribution and migration of the major taxa sampled during the investigation. An objective summary of the plankton data utilizing factor analysis and cluster analysis has been provided by Angel & Fasham (1973, 1974).
The Functional Anatomy and Development of the Swimbladder-Inner Ear-Lateral Line System in Herring and Sprat
Authors: Allen Jennifer M. , Blaxter J. H. S. , Denton E. J.
Published: May 2009

INTRODUCTION

The herringClupea harengusL. and spratSprattus sprattus(L.) are physostomatous teleosts with narrow ducts connecting the swimbladder to both the gut and cloaca. With other clupeoids these two species were of great interest to the anatomists of previous generations because of the further tubular connexions between the swimbladder and air-filled otic bullae close to the labyrinth of the inner ear. Together with the Ostariophysi, which have a chain of Weberian ossicles between the swimbladder and the inner ear, the clupeoids were thought to have enhanced hearing compared with many other teleosts as a result of coupling the ear to the swimbladder.

Despite such interest in the system the earlier literature is very fragmented, with the descriptions ranging over at least a dozen clupeoid species, and much of the work was done on fairly advanced juvenile or on adult fish. Ridewood (1891) examined the swimbladder-inner ear relationship in adult herring, pilchardClupea pilchardus, sprat, shadC. alosa, twaiteC. fintaand anchovyEngraulis encrasicholus; Tracy (1920) made a similar study of the American Atlantic clupeoids – the shadAlosa sapidissima, alewifePomolobus pseudoharengus, summer herringP. aestivalis, fall herringP. mediocrisand menhadenBrevoortia tyrannusand O'Connell (1955) of the Pacific sardineSardinops caeruleaand anchovyEngraulis mordax. Wohlfahrt (1936) considered the total swimbladder-inner ear-lateral line relationship in 100–120 mm pilchards, recognizing the much less obvious connexion between the perilymph and the lateral line through a membrane in the skull. The presence of such a connexion had been suggested earlier by Tracy (1920).