bluuebunny/crossref_metadata_2025 huggingface dataset:
Disappearance of the warm-water hermit crab Clibanarius erythropus from south-west Britain
Authors: Southward A. J. , Southward Eve C.
Published: May 2009

The hermit crab Clibanarius erythropus first reported from Britain in 1961 is no longer present. There appears to have been no further recruitment since the late 1950s when there was a favourable combination of climate and hydrographical factors that led to successful invasion of Devon and Cornwall.

The population appears to have succumbed to the combined effect of age and declining temperatures. Additional contributory factors in the decline could be the mortalities resulting from the ‘Torrey Canyon’ disaster; the reduction in numbers of the dog-whelk (whose empty shells are the favoured home of the crab in Britain) as a result of organotin antifouling paints; and increased public pressure on the habitat.
The Fauna of the Exe Estuary
Authors: Allen E. J. , Todd R. A.
Published: May 2009

In continuation of the scheme commenced last year for making a detailed survey of the marine fauna in the estuaries on the Devon and Cornish coasts, an examination has been undertaken during the present summer (1901) of the Exe estuary. For this purpose the floating laboratory bot Dawn, which has been generously placed at our disposal and maintained by Mr. J. W. Woodall, was towed to Exmouth and moored in the dock there, where she remained from July to September.
A New Method for Growing Hydroids in Small Aquaria by means of a Continuous Current Tube
Authors: Browne Edward T.
Published: May 2009

The simple piece of apparatus, to which I give the name “Currenttube” was made last year in the Marine Laboratory at Plymouth. I designed it especially for growing Hydroids, and for them it has proved to be a success; but it should also be useful for other fixed organisms, such as sponges, polyzoa, and ascidians.

The previous methods which I had used for growing Hydroids in bell-jars or small aquaria never gave complete satisfaction. Occasionally a success was recorded, but there were too many failures, which frequently involved a great waste of labour.
A Peculiarly Abnormal Specimen of the Turbot
Authors: Cunningham J. T.
Published: May 2009

The specimen which forms the subject of this note was sent to Dr. Allen by Miss Olivia L. Fox, of Falmouth, at the beginning of December, 1906, preserved in formalin. Dr. Allen sent it to me in London, and requested me to study and describe it. The specimen is 4·4 cm. in length, and presents a condition which has never previously been described in any species of flat-fish. I have examined it with great interest, and would express here my thanks to Dr. Allen for sending it to me.
On Phellia murocincta (Gosse)
Authors: Walton Chas. L.
Published: May 2009

P. H. Gosse described this beautiful little species in his British Sea Anemones and Corals, in 1860, from two specimens obtained from a pool at Petit Tor, near Torquay.

I recently collected two specimens at Zennor, some five miles along the coast south of St. Ives, Cornwall.

An examination of these proved that Gosse's examples were young and immature, as shown by the difference of size and number of tentacles.
Higginsia Ciccaresei sp. nov. (Porifera: Demospongiae) from a Marine Cave on the Apulian Coast (Mediterranean Sea)
Authors: Pansini Maurizio , Pesce Giuseppe L.
Published: May 2009

A new species of sponge: Higginsia ciccaresei sp. nov. (Demospongiae: Desmoxyidae) is described from a marine cave of the Ionian Apulian coast (Mediterranean Sea). It lives in complete darkness, 250 m from the cave entrance, in a basin of anchialine waters of low salinity and relatively cool temperature. The spicule formation process seems to be affected by some of the peculiar characteristics of the ambient water, resulting in spicules of unusual shape and irregular surface. This is the second record of the genus Higginsia – which has a world-wide distribution – from the Mediterranean Sea. The hypothesis that H. ciccaresei could be considered as a tethyan relic which survived in the peculiar habitat of an anchialine cave is also suggested.
Variability of Segment Number and Regeneration inSpiochaetopterus Solitarius. Comparison withS. Costarum(Polychaeta: Chaetopteridae)
Authors: Bhaud Michel R.
Published: May 2009

The variability in the number of segments in anterior (A) and median (B) regions of adult-size specimensSpiochaetopterus solitarius(Chaetopteridae), was examined in the present study. Variability of region A is considered in relation to the number of specialized setae in A4, which varies from 2 to 4; variability of region B is observed as a decrease in the number of segments during a limited part of the year. A process involving autotomy and regeneration has been advanced to explain the variability in the number of segments in region B. It appears that, once the number of segments in region B reaches a certain level, which is close to 30, the animal divides within region B, and the missing parts of each section are then regenerated. The maximum number of segments in region B may be considered to be species specific and used as a discriminative feature in the genus. It is suggested that regeneration does not reflect asexual multiplicationper se, but provides a means to facilitate the supply of energy to region B, which is responsible for bringing the products of the sexual organs to maturity. Consequently, regeneration is considered to complement sexual reproduction, facilitating the availability of energy to region B for reproduction. Implications of this variability have been examined by comparingS. solitariusandS. costarum, two species closely related by their morphology, sympatry and syntopy.
Osmotic and Body Density Response in the Harpacticoid CopepodTigriopus Brevicornisin Supralittoral Rock Pools
Authors: McAllen R.J. , Taylor A.C. , Davenport J.
Published: May 2009

Studies of the osmotic and ionic responses of the supralittoral rock pool inhabitantTigriopus brevicornis(Crustacea: Copepoda) showed that this species of orange harpacticoid copepod is an unusually euryhaline osmoconformer. Body fluid osmolalities were 297–3691 mOsm kg−1over a medium range of 151–3440 mOsm kg−1. Whole body sodium increased from 3·65 to 15·0 μmol Na+mg DW−1(dry weight) over the medium range 80–1900 mM Na+. Comparative studies onArtemianauplii and the prawnPalaemon elegansrevealed the characteristic hyper-hyporegulation of both organisms. Body density of T.brevicornisremains greater than that of the external medium over the salinity range 5–100 psu because of changes in body fluid osmolality and body volume. Median body density values for T.brevicornisranged from 1·0359 g ml−1in 5 psu (median density of 5psu seawater–1·0017 g ml−1) to 1·0848 g ml−1in 100 psu (median density of 100 psu seawater=1·0751 g ml−1).Tigriopus brevicornisis principally a benthic forager and needs to remain negatively buoyant over a wide salinity range. Environmental monitoring of five supralittoral rockpools was conducted over a year. Live or dormantT. brevicorniswere found in salinities of 4–150 psu; temperatures of −1 to +32°C and oxygen concentrations of 0 to >20 mg l−1. It is probably of advantage toT. brevicornisto be an osmoconformer; it is perhaps energetically efficient for such a small organism (~1 mm) and avoids buoyancy problems at high salinity.
Morphological Variability in Illex Coindetii (Cephalopoda: Ommastrephidae) Along the North-West Coast of Africa
Authors: Hernández-García V. , Castro J.J.
Published: May 2009

This paper gives morphometric variations and dorsal mantle length–total weight (DML-TW) relationships for Illex coindetii in the eastern Central Atlantic area. Positive allometry was observed in males and negative in females of the species. The most variable body measurements between males and females were width and perimeter of the head. In the study area, divergence of morphometric measurement starts at 95 mm. The point of divergence, however, varies with latitude; fluctuating from 104 mm in the north (Morocco and Sahara) to 76 mm in the central area (Mauritania and north of Senegal) and 73 mm in the south (Gulf of Guinea).

The relationships between DML and TW showed that sexual dimorphism due to differential growth between males and females starts to occur at 56 mm ML. The starting point of sexual dimorphism (56 mm) varies according to the zone; the higher the latitude, the later it occurs. Thus, sexual dimorphism occurs at 49 mm in the south (Gulf of Guinea), at 54 mm in the central area (Mauritania and north of Senegal) and at 74 mm in the north (Morocco and Sahara). Females grow larger than males, but males were heavier at any given length. As latitude decreased, a slow down in the increase in weight-at-length was observed in both sexes.
Benthic Egg Masses and Larval Development of Amblyosyllis Speciosa (Polychaeta: Syllidae)
Authors: Pernet Bruno
Published: May 2009

Eggs of the syllid polychaete Atnblyosyllis speciosa are deposited in benthic gelatinous masses. Embryos and larvae develop within these masses until about three weeks after fertilization, after which they crawl or swim away and metamorphose. Only one other syllid, the Mediterranean Syllides edentula, has been reported to form benthic egg masses.

While some syllid polychaetes spawn gametes freely into the water column where they are fertilized and develop without additional parental care, most species protect developing embryos in some fashion. Four modes of brood protection have been reported in the syllids. Protection of embryos within the ventral brood chamber of a planktonic adult is characteristic of members of the subfamily Autolytinae, and of some members of the Eusyllinae (Garwood, 1991). Physical attachment of embryos to the body of the maternal parent (external gestation) occurs in all members of the Exogoninae and in a few eusyllines (Heacox & Schroeder, 1978; Garwood, 1991). Viviparity is less common, having been reported in a few species in the subfamily Syllinae (Schroeder & Hermans, 1975; Ben-Eliahu, 1975) and in one exogonine (Pocklington & Hutcheson, 1983). Finally, the formation of benthic egg masses has been described in only one species, the eusylline Syllides edentula Claparède (Cognetti-Varriale, 1971).

In this study the benthic egg masses and development of another eusylline, Amblyosyllis speciosa Izuka, 1912, are described. In December 1995, at the Friday Harbor Laboratories (FHL), Washington, USA, five adult worms were found on a bivalve shell heavily infested with the boring sponge Cliona sp. Additional specimens and egg masses were collected in June 1996 and April-June 1997 from encrusting sponges on the FHL breakwater.
A Survey of Shellfish Toxicity in the Central Adriatic Sea
Authors: Marasović Ivona , Ninčević Živana , Pavela-Vrančič Maja , Orhanović Stjepan
Published: May 2009

The first data substantiating the occurrence of diarrhetic shellfish poisoning (DSP) in the central region of the Adriatic Sea (Kaštela Bay) in the summer of 1995 is presented. Toxicity was investigated using bio-assay and HPLC-FD analysis. Analysis of samples displaying toxicity, in addition to small concentrations of okadaic acid (OA), suggested the presence of an unknown derivatized compound at high concentration. A long term survey of the phytoplankton community has been conducted. The origin of mussel toxicity was traced to Dinophysis sacculus, a suspected toxic species.
Predation on Juvenile Lagoonal Mud Snails (Hydrobia Neglecta)
Authors: McArthur Victoria E.
Published: May 2009

Lagoonal mud snails have been shown to suffer approximately 50% mortality between hatching and adulthood. Experiments were conducted in the laboratory to assess the role of predators on the survival of juvenile Hydrobia neglecta (Mollusca: Gastropoda). Adult snails were collected from a lagoon in the Reedland Marshes system at Dunwich, Suffolk, and their eggs hatched in the laboratory, providing a population of juvenile snails which could be presented as a food source. The vessels, kept at environmental regimes close to that of the natural environment, were seeded with juvenile snails at field density. Predator preference was established by exposing the juvenile snails to combinations of potential predators found in the lagoon. One experiment also gave predators a choice of various juvenile snail sizes and other prey species. Juvenile snails remaining alive after the four week exposure to predators were removed, counted and measured. In the absence of other prey, the opisthobranch snail Retusa obtusa preferentially consumed 50% of the available juvenile H. neglecta over a four week period and the nemertean Lineus ruber up to 90%, making them the major contributors to juvenile H. neglecta mortality. The infaunal anemone Nematostella vectensis, did not have a significant impact on snail survival in the experiments but was observed (incidentally) in a separate non-experimental situation engulfing juvenile H. neglecta. The stickleback Gasterosteus aculeatus and the lagoonal prawn Palaemonetes varians, did not contribute directly to the observed mortality of juvenile mud snails, but were found to consume other predators, producing a system of prey preferences in the food chain. Understanding the role of predation contributes to the understanding of ecological processes occurring in rare lagoonal systems.
The Rate of Liberation of Phosphate in Sea Water by the Breakdown of Plankton Organisms
Authors: Cooper L. H. N.
Published: May 2009

Samples of animal and plant plankton were added to sea water in glass vessels and the subsequent changes in the phosphate content of the water were followed.

The breakdown of the zooplankton was very rapid and more phosphate was set free than had originally been added as plankton. The balance was produced from dissolved organic phosphorus compounds in the water. The breakdown of phytoplankton showed a short time lag and only a part of the phosphorus added was set free as phosphate.
The Ecology of a Salt–Marsh
Authors: Nicol A. T.
Published: May 2009

The salt-marsh under investigation is situated at Aberlady Bay on the south shore of the Firth of Forth, fifteen miles east of Edinburgh.

The marsh is small and occurs at the mouth of a stream. The character of the soil on the two banks differs, being on the one side muddy with permanent pools, and on the other sandy, so that the pools tend to drain dry. The vegetation of the pools is variable, some containing species of Zostera, Ulva, Enteromorpha and Vaucheria, others having only diatoms.
Laboratory studies of gregarious settlement inBalanus balanoidesandElminius modestusin relation to competition between these species
Authors: Barnett B. E. , Crisp D. J.
Published: May 2009

Settlement behaviour of barnacle cyprids has been investigated extensively. There are two opposing tendencies. The cyprids settle gregariously over distances of several centimetres (Knight-Jones, 1953a,b; Knight-Jones & Stevenson, 1950; Knight-Jones & Crisp, 1953; Crisp & Meadows, 1962,1963). However, at closer range of a few millimetres they tend to space themselves out (Crisp, 1961; Knight-Jones & Moyse, 1961).
Absence of gregarious settling Behaviour by female cypris larvae of British parasitic rhizocephalan barnacles
Authors: Rainbow P. S. , Ford M. P. , Hepplewhite I.
Published: May 2009

Barnacle cypris larvae, the specialized settlement stage of the life-cycle, are classical examples of larvae showing gregarious settlement. Gregarious settlement is shown when the larva is induced to settle by established individuals of its own or of a closely related species, reflecting the ability of the larva to recognize its own type, usually by chemo-tactile detection of a particular settlement inducing factor (see Crisp (1974) for review). Sessile barnacles such as species of Balanus or Chthamalus are typically hermaphrodite and gregarious settlement is of selective advantage in promoting the possibility of cross-fertilization, in addition to allowing a settling larva to identify a habitat providing all the necessary conditions for barnacle growth and development.
Host-Adoption in the Commensal Polychaete Nereis Fucata
Authors: Gilpin-Brown J. B.
Published: May 2009

The adults ofNereis fucata (Savigny) are commensal with hermit crabs and live within the upper whorls of the shells of their hosts. The mechanism of host adoption has been examined in juveniles reared in the laboratory. There are two distinct phases in their response to their host. The first is a searching phase during which the anterior two-thirds of the worm is extended from the tube and makes wide sweeping movements in its immediate vicinity. This phase can be initiated in the laboratory solely by vibrations in the substrate; the presence of a hermit crab is not required. The second phase begins as soon as a suitable gastropod shell is touched, when the worm immediately leaves its tube and enters the shell. In the laboratory this phase can be achieved without the presence of a hermit crab, so that it is presumably primarily dependent upon the tactile stimuli received from the surface of the shell. It is argued that in nature only hermit-crab shells would commonly give this combination of stimuli to the worm and that the association betweenNereis fucata and hermit crabs is not accidental but commensal.
A New Punctate Species of Halosphaera
Authors: Boalch G. T. , Mommaerts J. P.
Published: May 2009

The new species Halosphaera parkeae (Prasinophyceae) is described from material collected in the western English Channel. The microscopical structure of the outer wall of the non-motile phase is described and two types of punctation are demonstrated. A general account of the cytology of the mature non-motile phase and of the motile cell is given. Electron micrographs of the scales of the motile cell are compared with those of other species of the genus where known. Buoyancy, size and reproduction are discussed and a number of new taxonomic characters emphasized. The occurence in the same areas of a second type very similar but smaller in size is recorded and the authors have named this form Halosphaera parkeae forma minuta.
Tunny Investigations made in the North Sea on Col. E. T. Peel's Yacht, “St. George,” Summer, 1933. Part I. Biometric Data
Authors: Russell F. S.
Published: May 2009

1. Details are given of the types of hooks lost in tunny in the North Sea in the summer of 1933.

2. Data are given on the measurements made on thirty-two large migrating fish caught in the North Sea in August and September, 1933.

3. In certain body proportions the tunny measured differ from those in the G4 Group (200 to 260 cm. in length) given by Heldt for fish from Tunis and by Frade for fish from Algarve on the south coast of Portugal, while in some characters they resemble the Tunis fish and in others the Algarve fish, but all the North Sea fish were between 232 and 271 cm. in length.

4. It was found that there was a tendency for fish with short second dorsal fins to have short first dorsal, anal, and caudal fins, and for those with long second dorsals to have these other three fins long.

5. Measurements were made to supply data on the condition of the fish.
Variations in the Amount of Macroplankton by Day and Night
Authors: Gardiner A. C.
Published: May 2009

1. Twenty oblique hauls of a stramin ring-trawl, diameter of mouth 5 feet, were made during a period of 48 hours off Liverpool, Nova Scotia, i n May, 1932.

2. The common species were Thysanoëssa mschii, Th. inermis, Sagilta elegans, Calanus finmarchicus and C. hyperboreus.

3. All of the above occurred in the collections made during the night n i larger numbers than in those in the daytime. No such discrepancy appeared in the case of the Fish Ova.

4. The discrepancy is held to be due in each case to a proportion of the population sinking to depths greater than could be sampled by the net.
The Habitat ofProcerodes uluœ
Authors: Ritchie A. D.
Published: May 2009

Procerodes ulvœhas been found living in streams with calcium content as low as 5 mgm. per litre. Its upper limit does not appear to be affected by the calcium content of the water. The animals at the upper limit are liable to about 5 days' exposure to fresh water if calm weather coincides with Neap Tides. Animals living in water of 8–12 mgm. Ca per litre have been found alive at the end of such a period.
The Use of a Selenium Rectifier Photo-electric Cell for Submarine Photometry
Authors: Poole H. H. , Atkins W. K. G.
Published: May 2009

1. Measurements of the penetration of light of various colours into the sea were carried out by means of a selenium rectifier cell. The mean vertical absorption coefficients were: for blue, 0·177; green, 0·153; “white,” viz. no filter, 0·216; yellow, 0·243; red, 0·345. The results accord well with those obtained under similar conditions with emission cells and show that, for water a couple of miles offshore, green light penetrates best.

2. The current was measured using the potentiometer-telephone method as for emission cells, but determining the drop in potential across a low resistance, 10,100, or 1000 ohms. The motion of the ship was too violent to permit of the use of any available galvanometer of adequate sensitivity.

3. Rectifier cells are more convenient to use than emission cells, as the currents to be measured are much larger and the absence, of high potentials greatly simplifies all insulation problems. On the other hand the curvature of the illumination–current relation involves additional labour in standardizing and in calculating results.
An experimental study of the pattern and significance of the climbing behaviour of Hydrobia ulvae
Authors: Barnes R. S. K.
Published: May 2009

The climbing behaviour of the gastropod Hydrobia ulvae (Pennant) and its relationship with flotation/dispersal were investigated by field observations and experiments in Norfolk, U.K. and by laboratory experiments. Field experiments of the type used by previous authors were discontinued when it was observed that counts at low tide of snails which had climbed objects the previous high tide did not reflect adequately climbing activity during that period of tidal cover. Both field and laboratory studies yielded five general results: (i) snails climbed only when covered by tidal water; (ii) climbing activity was not related to population density; (iii) climbing activity, under conditions of constant population density, varied markedly during the cycle of spring tidal cover, reaching a peak after the first few tides and declining rapidly thereafter; (iv) maximum numbers of snails were present on submerged structures relatively early in any given period of cover and declined (snails crawled downwards off the structure) as the period of cover continued; and (v) rarely were large proportions of climbed Hydrobia floated off their support by the incoming tide; this was associated only with conditions of extreme calm.
Long-term trends in the distribution, abundance and seasonal occurrence of larvae of mackerel (Scomber scombrus L.) around the British Isles, 1948–1978
Authors: Coombs S. H. , Mitchell C. E.
Published: May 2009

The distribution, abundance and seasonal occurrence of larvae of mackerel (Scomber scombrus L.) are described from routine Continuous Plankton Recorder (CPR) sampling around the British Isles over the period 1948–78, and from more intensive CPR sampling in the Celtic Sea in 1977. There were two main areas of larval concentration: in the North Sea and over and adjacent to the Celtic Plateau; subsidiary aggregations were observed to the northwest of Ireland and to the west of Norway. There were some similarities between the distribution of larvae around the British Isles and that of adult Calanus spp. In the North Sea there was a southerly shift of larval distribution over the period 1948–77; over a similar period the abundance of larvae increased to reach high numbers by the late 1950s and subsequently declined after the mid-6os. To the south-west of the British Isles numbers of larvae showed a long-term decline. The long-term trends of distribution and abundance are discussed in relation to concurrent biological and environmental change. The clearest relationship was found between the numbers of mackerel larvae in the North Sea and sea-surface temperature in the North Atlantic, which suggests a common causative agent for both sets of observations; also, there was a weak relationship with both spawning stock biomass and sea-surface temperature at the spawning areas. In the North Sea the seasonal occurrence of larvae was from May to August, the majority being taken in June and July; over the period 1948–77 the seasonal time of occurrence of highest numbers of larvae has remained relatively constant. In the Celtic Sea the seasonal occurrence of larvae was spread over a longer period, from March to August, with relatively high numbers from March to June; over the period 1950–78 the time of occurrence has been variable, possibly with a tendency towards later timing in more recent years.
The Population cycle of the bivalve Abra tenuis and its mode of reproduction
Authors: Gibbs P. E.
Published: May 2009

The annual cycles of the Abra tennis populations in the Plym Estuary and the Fleet (Dorset) were studied from March 1980 to June 1982. In the Plym Estuary the highest numbers occurred in autumn following juvenile recruitment and the lowest numbers were recorded in mid-summer. In the Fleet such an annual cycle in numbers was not apparent since juvenile recruitment in 1980 was very high but in 1981 it was very low. The recruitment failure in 1981 may have resulted, at least in part, from the heavy summer infection of A. tenuis by digenean parasites that destroy the gonads of the host, thereby reducing the population fecundity.

A. tenuis spawns in July and August: the mature egg has a diameter of 140 μm and is enclosed in a sticky gelatinous envelope. Females produce 450–1800 eggs which, when fertilized, are laid in a mass within the sediment and, following a direct development, the juveniles hatch as miniature adults after 2–3 weeks. This non-pelagic, lecithotrophic development is interpreted as being a means of ensuring the maintenance of populations within restricted estuarine habitats. Data suggest A. tenuis lives for 1 or 2 years and that the species is monotelic.
Summer vertical distribution of appendicularians in the central Cantabrian Sea (Bay of Biscay)
Authors: Luis Acuña José
Published: May 2009

The summer vertical distribution of appendicularian species was analysed at 22 stations in the central Cantabrian Sea by means of vertical tows covering the surface, thermocline and deep layers. According to their preference for shallower waters, the appendicularian species could be arranged on the series Oikopleura longicauda (Vogt), Oikopleura fusiformis (Fol), Fritillaria pellucida (Quoy & Gaimard) and Oikopleura rufescens (Fol), with Oikopleura dioica (Miiller) in an uncertain position, probably closer to the end of this series. Principal components and correlation analyses suggest that a temperature gradient causes this pattern, which agrees with previous findings made at very different temporal and spatial scales. By means of particle-size spectra, it is shown that those oikopleurids that prefer cold, deep waters, O. fusiformis and O. rufescens, co-vary with a coefficient of particle-size quality. The lower the temperature, the lower the proportion of small, ingestible particles to large inlet-filter-clogging particles. This is proposed as an important reason for the presence of inlet filters in oikopleurids.
Nutrient stimulation of carbon fixation in summertime English Channel phytoplankton assemblages
Authors: Davies Anthony G. , Sleep Jillian A.
Published: May 2009

The effects of nutrient additions and zooplankton excretion products upon carbon fixation rates in the phytoplankton present at Station L 4 in the English Channel during the summer and autumn of 1979 have been studied. Nitrate, ammonium, urea, phosphate, glucose-6-phosphate and the excretion products when added individually all caused photosynthesis to be stimulated, and the result of the simultaneous addition of nitrate and phosphate indicated that their effects were additive. Germanic acid, which inhibits photosynthesis mainly in diatoms, removed the stimulatory effect of the nitrogen supplements, indicating that they were utilized mostly by the diatoms; the higher fixation rates caused by the phosphate enrichments were, however, decreased by the same proportion as the unenriched controls when germanic acid was present, suggesting that the whole of the phytoplankton population was phosphorus-limited. This was supported by the finding that glucose-6-phosphate stimulated carbon fixation in all of the phytoplankton.

The excretion products, even at concentrations likely to be produced in the sea, stimulated carbon fixation, and it has been calculated that zooplankton-regenerated nitrogen and phosphorus compounds could supply the amounts needed to maintain primary production during the summer period.

Nutrient additions and zooplankton excretion products had little effect upon carbon fixation in the autumn samples, presumably because the higher nutrient levels then present in the water exceeded the requirements of the phytoplankton.

It has been concluded that the predominance of the sub-10μmicroflagellates in the summertime is probably due to their ability to utilize more efficiently than the other types of phytoplankton the low levels of nutrients which become available due to regeneration.
Notes on the Respiratory Mechanism of Corystes Cassivelaunus
Authors: Zimmermann Kathleen E.
Published: May 2009

Corystes buries itself in sand for protection, with the tip of the antennal tube, through which enters the respiratory current, projecting. The water which enters the antennal tube cannot be quite clear: there is a hairy filter, which rejects particles of mud, etc., at the entrance to each branchial chamber. The main body of the in-current is split into right and left currents, owing to the position of the apophyses of the mandibles, and these two currents enter respectively the right and left branchial chambers. The epistomial ridge on the roof of the prostomial chamber turns aside some portion of the in-current, which portion passes out ventrally through a gap in the floor of the chamber, carrying out with it foreign particles brought in by the in-current and rejected by the sieves guarding the entrances to the branchial chambers.
An Account of the Natural History of the Slipper-Limpet: (Crepidula fornicata),: With some remarks on its occurrence on the Oyster Grounds on the Essex Coast
Authors: Orton J. H.
Published: May 2009

The American limpet, or slipper-limpet, known to naturalists as Crepidula fornicata, was introduced into England about 1880, being recorded at that time by Mr. B. S. Dodd in the Proceedings of the Malacological Society for 1893. Dodd, it is interesting to note, sounded even at that early time a warning note against the possible spread of this animal, and the probability of its becoming an enemy to the oyster farmer. There is no doubt that this limpet has been, and is probably still being introduced along with American oysters, on which it fixes itself. I have myself seen it unshipped along with oysters, but all the specimens I found had died recently. The spread of the limpet appears to have been very rapid on some grounds, as, for example, at West Mersea, where, since its appearance about eight years ago (from information obtained from local oyster fishermen), it has spread so that it is now more common than oysters.
The Loss of the Eye-pigment in Gammarus chevreuxi. A Mendelian Study
Authors: Allen E. J. , Sexton E. W.
Published: May 2009

Sections I and II. Amongst the stock of Gammarus chevreuxi which had been kept under Laboratory conditions for at least two years a small number of animals appeared in which the coloured retinal pigment was absent, whilst the white extra-retinal pigment remained. The experiments described in the present paper have shown that these eyes were of two different kinds.

Eyes of the first kind were derived from a stock which originated in a cross between Black-eyed and Red-eyed animals, and were degenerate and irregular in shape. Four animals of this kind appeared in one brood, and such eyes have since been seen only in direct descendants from these. Eyes of this kind were found to behave as simple Mendelian recessives to eyes showing coloured retinal pigment, whether that pigment was red or black, and they are referred to in this paper as “albino” eyes.
Short-wave absorbing pigments in the ocular lenses of deep-sea teleosts
Authors: Douglas R. H. , Thorpe A.
Published: May 2009

This study describes the spectral characteristics between 250 and 700 nm of lenses from 71 species of deep-sea teleost. The majority of these did not contain detectable amounts of short-wave absorbing pigment and transmitted all longer wavelengths to the same extent before cutting off smoothly and rapidly in the near-UV (50% transmission 310–348 nm). The lenses of 15 species, however, contained significant amounts of short-wave absorbing pigment. The majority of these lenticular pigments had smooth ‘bell-shaped’ absorbance spectra with a single peak in the near-UV. Such ‘simple’ pigments were extracted from four species (λmax: 360·8 nm, 36·50 nm, 395·7 nm, 324·8 nm) and detected in a further eight species, although insufficient material was available to allow their extraction from the latter group.

The absorbance profiles of lenses from another three species were more complex, suggesting the presence of one and two carotenoid-like pigments respectively in the lenses ofArgyropelecus sladeniandA. affinis,and two as yet unidentified pigments in the lenses ofMalacosteus niger.This brings the total of short-wave absorbing pigments so far described in the lenses of deep-sea fish to at least eleven. InArgyropelecusspp. the pigmentation was most pronounced in the lens cortex, while inMalacosteus nigerit was restricted to the lens core. In all other species the pigment appeared freely diffusible throughout the lens. Several species showed an increase in the degree of lenticular pigmentation in older animals and two(Argyropelecus affinisandMalacosteus niger)demonstrated age-related changes in the relative concentrations of two different pigments within the lens.
Species composition of demersal fish in the Rockall Trough, north-eastern Atlantic, as determined by different trawls
Authors: Gordon J. D. M. , Bergstad O. A.
Published: May 2009

The variation in species composition of continental slope fishes as determined by the catches of different trawls towed either on single or paired warps was analysed by Detrended Correspondence Analysis (DCA). The catches of two trawls, a semi-balloon trawl (OTSB) and a Granton trawl (GT) were very similar when towed on paired warps. Significant differences were found between the catches of the OTSB trawl towed on single and paired warps. The DCA effectively provided information on the important gradients, e.g. depth, trawl type, and indicated which species were most abundant in the different depth zones and trawl types. Detailed accounts of the abundance and biomass of different species by trawl type and depth zone are given and the observed pattern of distribution discussed.
The visual pigments of a deep-water malacosteid fish
Authors: Crescitelli Frederick
Published: May 2009

The present investigation is a confirmation and extension of the idea that visual pigments adapted to the quality of their own bioluminescence have evolved in certain deep-water marine fishes. In this case a single fish (Malacosteus danae) of the family Malacosteidae, known to have red-emitting photophores, was trawled up in daylight from the Pacific off the coast of Southern California. Retinal extractions were found to contain two photopigments with absorbance maxima, one at 556 nm, the second at 514 nm. From the spectral positions of the oximes formed by bleaching in the presence of hydroxylamine it was inferred that the 556-pigment is an A2-pigment and the 514-pigment, an Aj-pigment. Evidence was also obtained from the effect of hydroxylamine on the unbleached extract of the possible presence of a photopigment that was bleached by the daylight when the fish was brought to the surface. This pigment, also identified as an A,-component from the oxime spectrum, could have been a moiety of the 514-photopigment but the possibility of a third visual pigment in the retina of this fish cannot be discounted. Except for this hydroxylamine effect the results are in agreement with published data from Aristostomias scintillans.
The Plymouth Mackerel Fishery of 1889—90. From Data collected by Mr. Wm. Roach, Associate Member M. B. A.
Authors: Calderwood W. L.
Published: May 2009

The returns kindly sent in by Mr. Roach have been tabulated in the following pages.

The period during which Mr. Roach made his observations extends from October 23rd, 1889, to September 29th, 1890.

Concerning the particular localities in which the fish have been caught, it may be useful, for those who are not familiar with the coast, to explain that the fish make their appearance on the coast at a considerable distance to the east of Plymouth (18—20 miles). The shoals then appear to travel in a westerly direction, some going off into deeper water, all moving about in a more or less uncertain manner. The head-quarters of the fishery eventually become fixed south of Plymouth and Eddystone Light. Gradually the fish seem t o approach the shore, swimming now in large shoals. Many enter Plymouth Sound and are taken in comparatively shallow water, while others travel west, also in shallow water. The “remarks” for August are instructive. We find that, besides the ordinary and large fish, there are also “small fish about the size of pilchards” in the Sound, that “numerous large shoals” are noticed, and that at a later date the fish “seem to be leaving Plymouth Sound.” On September 1st we find the note that “the mackerel are going off into open water and the shoals breaking up.” On the breaking up of the shoals the mackerel fishing is considered to be at an end.
The Immature Fish Question
Authors: Cunningham J. T.
Published: May 2009

It is only eight years since the Royal Commission on beam trawling issued its report, and already a Select Committee of Parliament has been appointed to make a new inquiry into one of the principal subjects investigated by that Commission, namely, the decrease of the fish supply and the advisability of remedial measures. Among the conclusions of the Commission was this one:
Monthly Reports on the Fishing in the Neighbourhood of Plymouth
Authors: Calderwood W. L.
Published: May 2009

The four charts produced in this number, showing as nearly as possible the positions of the various fishing boats in the neighbourhood of Plymouth, are a continuation of the series of charts already introduced in Nos. 3 and 4 of vol. ii. They represent the conditions found during last September, October, November, and December, and complete the year's observations.
Faunistic Notes at Plymouth during 1893–4.
Authors: Garstang Walter
Published: May 2009

The year 1893 was one of exceptional interest to the marine zoologist. During the first two months Plymouth experienced a continuous succession of heavy gales, but towards the middle of March the winds became lighter, and the sea, which had been running remarkably high outside the breakwater, subsided. From that time onwards till the middle of September we enjoyed six months of the most delightful weather,—a period, with scarcely a break, of calm seas and almost cloudless skies. Under the influence of the great heat the temperature of the Channel waters rose continuously, until in August it had attained a point unprecedented for quarter of a century; and it was of the highest interest to observe the effect of this high temperature, and of the prolonged calmness of the sea, upon the floating population of the neighbouring portion of the Channel. Numbers of semi-oceanic forms which rarely reach our shores arrived in remarkable profusion. In June the tow-nets were crowded with Salps, while towards the latter end of August they were almost choked by masses of living Radiolaria.
Fishery Publications of the United States
Authors: Cunningham J. T.
Published: May 2009

In recent years the Bulletin of the United States Fish Commission has outgrown its older brother, the Report of the Commissioner, and in some respects supplanted it. The last volume of the Report, part xvii, bears the date of publication 1893, but it was only received by us in the present month of June, 1894, and it refers to operations carried out in the two years 1889–91,—in other words, from three to five years ago. The volume consists of three general reports and six appendices. The former are the Report of the Commissioner, that of Mr. Richard Rathbun on the Inquiry respecting Food-fishes and the Fishing-grounds, and that of Mr. Hugh M. Smith on the Inquiry regarding the Methods and Statistics of the Fisheries. The Appendices comprise three special reports, a Review of Sparoid Fishes, by David Starr Jordan and Bert Fesler, an article on Fish Entozoa, and a translation of Haeckel‘s well-known pamphlet, Plankton-Studien.
Lipid solubility of heavy metals in saline solutions
Authors: Simkiss K
Published: May 2009

Oil/water extraction systems have been devised to study the lipid solubility of metal ions in sea water. Group B metals such as Cu, Zn, Cd, Hg appear to form inorganic complexes in saline solutions that are very lipid soluble. The implications of this are discussed in terms of the penetration of metals across cell membranes.
Squalotrema llewellyni gen.nov., sp.nov., a monocotylid monogenean from the nasal fossae of the spur-dog, Squalus acanthias, at Plymouth
Authors: Kearn G. C. , Green J. E.
Published: May 2009

A description is given of Squalotrema llewellyni gen.nov., sp.nov., a monocotylid monogenean from the nasal fossae of the spur-dog Squalus acanthias. The parasite differs from representatives of other monocotylid genera in the number and arrangement of loculi on the haptor. In order to accommodate the genus Squalotrema, the diagnosis of the subfamily Merizocotylinae (Yamaguti, 1963) has been amended.

The eggs differ in shape from those of other monogeneans. Each egg appears to be derived from a tetrahedron by flattening of one of the four apices. A long, coiled appendage projects from the flattened apex and the face of the egg from which the appendage projects also bears two spurs. The curved body of the fully developed, ciliated oncomiracidium occupies only two of the three rounded corners of the egg.
Changes in the major dihydroporphyrin plankton pigments during the spring bloom of phytoplankton in two Scottish sea-lochs
Authors: Gowen R. J. , Tett T. , Wood B. J. B.
Published: May 2009

A chromatographic/fluorcmetric method was used to measure changes in the proportions of four planktonic dihydroporphyrin pigments during the spring bloom of 1979 in two f jordic sea-lochs, Creran and Etive, on the west coast of Scotland. Very little pheophytin a was detected during the bloom. Chlorophyll a, and to a lesser extent chlorophyllide a, were the two main pigments found during the bloom. During senescence the main pigment breakdown route appeared to be via chlorophyllide a to pheophorbide a. These results suggest that standard methods for measurement of ‘chlorophyll’ which do not distinguish between chlorophyll a and chlorophyllide a might significantly over-estimate the photosynthetic potential of phytoplankton.
Observations on the hydroids Coryne pintneri and Thecocodium brieni new to the British list
Authors: Edwards C. , Harvey S. M.
Published: May 2009

The athecate hydroids Coryne pintneri Schneider and Thecocodium brieni Bouillon, previously unreported from British waters, have been found near Oban, western Scot-land. Descriptions and figures are given, with observations on behaviour in culture. It is considered that Coryne pintr.eri is specifically distinct from Coryne filiformis (Rees). The feeding response of Thecocodium brieni is described, and it is concluded that it ismediated chemically by diffusion of exudate from captured prey. Response to mechanical stimulation is also described: it evidently is transmitted through the stolonal network, but it is not known whether this is via nervous or non-nervous tissue. The occurrence in Scotland of thesetwo species, previously known only from north-west France and the Mediterranean, is attributedto their probable introduction on oysters from Brittany, France.
The female reproductive cycle of the octopus,Eledone cirrhosa
Authors: Boyle P. R. , Knobloch Daniela
Published: May 2009

Changes in the relative size of the ovary, oviducal glands and eggs are described forEledone cirrhosacaptured from the North Sea off Aberdeen over a 3 year period(N= 488). The analysis is based only on freshly caught animals, excluding those held in aquarium conditions (> 5 days). Ovary enlargement and egg size estimates are used as indices of sexual maturity. Between 0–15% and 18–95% of total body weight is contributed by the ovary. Maximum egg length in the ovary ranges up to 7 mm. On these criteria, sexual maturation typically occurs at body sizes between 400–1000 g although some animals of 1000–1200 g are found showing no evidence of ovary enlargement. The majority of the monthly sample is always immature but maturation can apparently occur at almost any time of the year. Increase in mean ovary index and mean values for egg size are strongly seasonal and indicate a peak incidence of sexual maturity over 2–3 months in the July-September period. Spawning is presumed to follow within 1 month. Estimates of the fecundity of the females, based on the egg sample from the ovary, range from 2·2 × 103 to 55 × 10 3 eggs with a mean of 11 × 10 3 and a mode of 7·5 × 10 3 eggs.
Life-history and ultrastructure of a new marine species ofProterospongia(Choanoflagellida)
Authors: Leadbeater Barry S. C.
Published: May 2009

The morphology and microanatomy of two different phases in the life history of a single new marine choanoflagellate(Proterospongia choanojunctasp.nov.) have been documented and described with the aid of light microscopy and from electron microscopy of whole mounts and sections of material in clonal culture. Completion of the life-cycle has been repeatedly achieved in cultures established from single cells, regardless of which phase is used as a starting point. One phase is colonial and motile (theProterospongiaphase) and the other unicellular and sedentary (theChoanoecaphase). Taxonomic, nomenclatural and developmental problems are summarized and discussed.
Metaxymolgus longicauda (Claus), a copepod associated with the cuttlefish, Sepia officinalis L.
Authors: Ho Ju-Shey
Published: May 2009

Based on the morphology of the mandible, female maxilliped, and male first endopod, Lichomolgus longicauda (Claus) is transferred to Metaxymolgus Humes & Stock, 1972. M. longicauda is recorded for the first time from Sepia officinalis L. taken in British waters.
A new species of Halistemma (Siphonophora: Physonectae: Agalmidae) collected by submersible
Authors: Pugh P. R. , Youngbluth M. J.
Published: May 2009

A new species of physonect siphonophore, Halistemma transliratum sp. nov., is described from two specimens collected at mesopelagic depths in Bahamian waters by the submersibles ‘Johnson-Sea-Link’ I and II, and comparisons are made with the established species of that genus.