bluuebunny/crossref_metadata_2025_split huggingface dataset:
Observations on an endozoic red alga
Authors: Boney A. D. , White E. B. 
Published: May 2009

A description is given of a filamentous red alga which was found growing within a sponge collected from the sublittoral off Santander, Spain. The plant appears to be closely related to Acrochaetium spiculiphilum Dawson. A survey is given of the specific characters available for the typification of the known partially and completely endozoic Acrochaetium species, and some suggestions made on the more important lines of study.IntroductionDuring the summer of 1957 some specimens of the keratinous sponge Haliclona were collected from the sublittoral off Santander, Spain, by Mr G. R. Forster. Certain of the specimens bore extensive areas of red, and on preliminary examination this colour was found to be due to the filaments of a red alga showing an extensive ramifying growth within the skeleton of the sponge. The drawings and cell measurements to be reported were made from the plant material by A. D. B. soon after its collection. This information has been retained pending a more comprehensive study of endophytic and endozoic red algae. Work is now in progress on these lines (mainly by E. B. W.), and a re-examination of the Santander material has enabled us to make a critical study of the data available for a precise typification of plants of this habit. Further, since the association of endozoic filamentous red algae with sponges appears to be of rare occurrence, any examples need to be fully described.Description of PlantThe cells were of variable shape and size, and contained much-dissected parietal chromatophores (Fig. 1 a). Individual filaments tended to be closely packed together within the host (Fig. 1 b), and there was no extensive growth of erect filaments outside of the host material.
Nutritional value of dried algae diets for larvae of Manila clam(Tapes philippinarum)
Authors: Laing Ian , Child Anthony R. , Janke Achim 
Published: May 2009

Spray-driedNannochlorissp. andTetraselmis suecicawere fed to larvae of the Manila clam(Tapes philippinarum).These dried diets supported growth equal to, or greater than, their live algal counter-parts, but less than a control diet, a mixture of two algae species of known high nutritional value(Chaetocems calcitransand T-ISO).Larvae were grown through to metamorphosis on the driedNannochlorissp. diet in 21 days, compared with 8–11 days with the control diet. Using driedNannochloris, it was shown thatT. philippinarumlarvae do not have an essential requirement for long-chain (20 and 22C) polyunsaturated fatty acids, but are able to synthesize them from shorter chain (18C) fatty acids present in the diet. The higher total carbohydrate content of the dried algae was reflected in the larvae feeding on this diet.
Skeletal growth bands in brittle stars: microstructure and significance as age markers
Authors: Gage J. D. 
Published: May 2009

Skeletal growth banding has been studied in the vertebral arm ossicles of the shallowwater brittle stars Ophiothrix fragilis, Amphiura filiformis, A. chiajei, Ophiura ophiura and O.albida collected from near Oban. Scanning electron microscopy of ossicle microstructure show the bands reflect differences in stereom porosity and surface relief on the surface of the wing-like fossae of the ossicle. The evidence supports the interpretation of the bands as annual growth markers, with coarse-pored stereom laid down during periods of active growth in summer/autumn whilst finer-pored stereom, that often forms ‘breaking wave’- like ridges, is formed during periods of slow or negligible skeletal growth during the rest of the year. Growth curves fitted to growth ring measurements indicate three contrasting growth strategies amongst the species examined. These data generally support recent interpretations of demographic structure reached from studies of size frequencies in samples collected from other areas in the NE Atlantic range of these species.
Temperature-dependence of fish muscle AMP-aminohydrolase
Authors: Makarewicz W. 
Published: May 2009

The effect of temperature on the rate of reaction catalysed by crude muscle AMP-aminohydrolase from two species of elasmobranch and two species of teleost fish has been investigated at low substrate concentration in the range of temperature 5–50 °C.The enzyme from teleost fish shows a very broad temperature optimum around 30 °C. The reaction rate of the enzyme from elasmobranch fish is strongly dependent on temperature. The optimum temperature for the enzyme from thornback ray lies around 40 °C. Both crude and 500-fold purified AMP-aminohydrolase from thornback ray show the same temperature-dependence.
Nassarius reticulatus (Nassariidae: Gastropoda) as an indicator of tributyltin pollution before and after TBT restrictions
Authors: Bryan G. W. , Burt G. R. , Gibbs P. E. , Pascoe P. L. 
Published: May 2009

Between 1984 and 1993, levels of imposex (the induction of male characters including a penis on females) were measured in gastropods Nassarius (Hinia) reticulatus (L.) at localities in south-west England. Since tributyltin (TBT) was thought to cause imposex, concentrations in tissues and sea-water were also determined. Measurements made prior to the restriction of TBT usage in 1987 showed that intensities of imposex were related to TBT levels in females. Tissue concentrations were also related to those of sea-water and concentration factors (dry tissue/water) were approximately 30,000 at 10 ng Sn I-1 and 75,000 at 1 ng Sn I-1. Penis development in females was initiated at about 1 ng Sn I-1 and in this respect JV. reticulatus appears less sensitive to TBT than the dog-whelk Nucella lapillus.As result of the TBT restrictions, concentrations in sea-water and tissues at some of the more polluted sites decreased by factors of 5–10 times between 1987 and 1993. However, population imposex declined very slowly. This was attributed to the longevity of the snails, the slow decline of penis-length in older females and the limited recruitment of less-affected females.It was concluded that N. reticulatus is a useful alternative to N. lapillus as an imposex-based TBT indicator at contaminated sites. However, when environmental TBT concentrations are declining fairly rapidly, analysis of N. reticulatus tissues provides a far better indication of change than measurements of population imposex.
Statolith Microstructure and Maximum age of Loligo Gahi (Myopsida: Loliginidae) on the Patagonian Shelf
Authors: Arkhipkin Alexander 
Published: May 2009

Statoliths of Loligo gahi were sampled in the fishery region 45–47°S on the Patagonian shelf during September 1989. Peculiarities of the growth zones in the ground statoliths of adults are described. Maximum age of large maturing and mature females (130–160 mm of mantle length, ML) was estimated to be 325–345 d, that of large mature males (250–290 mm ML) ranged from 360 to 396 d.The squid Loligo gahi d'Orbigny, 1835, occurs in temperate shelf and upper slope waters of the Atlantic and Pacific coasts of South America and is caught commercially by the international fleet in the southern part of the Patagonian shelf within the Falkland Islands Interim Conservation Zone (FICZ) (Roper et al., 1984; Csirke, 1987). Occasionally, dense shoals of L. gahi appear in the fishery region 45–47°S off the Exclusive Economic Zone of Argentina (EEZA) and have been caught in significant numbers by trawlers at depths of 120–150 m in September-October (Chesheva, 1990). Loligo gahi is a medium sized loliginid; in Falkland waters males attain 350 mm ML, females 210 mm ML (Hatfield, 1991), while in the fishery region 45–47°S maximum size is 260 mm and 160 mm, respectively (Chesheva, 1990). Patterson (1988) revealed two Falkland spawning stocks of L. gahi of unclear status, spring-spawners and autumn-spawners (austral seasons) and pointed out that the life span of squid of each stock lasted ~1 y. Recently Hatfield (1991) used statoliths to elucidate Patterson's (1988) estimations of age and growth of Falkland stocks of L. gahi and confirmed the 1-y duration of L. gahi's life span.
Spiracular Gills in the Marine Fly Aphrosylus and their Relation to the Respiratory Horns of Other Dolichopodidae
Authors: Hinton H. E. 
Published: May 2009

The larva of the dolichopodid fly Aphrosylus celtiber Haliday is an omnivorous carnivore in the intertidal zone. It pupates in an air-filled cocoon of debris and a secretion of the labial glands. The pupa has plastron-bearing spiracular gills that have been evolved from respiratory horns similar to those of recent terrestrial Dolichopodidae.Although the spiracular gills are pupal structures, they are the chief respiratory organs of the young adult, i.e. the pharate adult, before it emerges from the cocoon. At the pupal-adult apolysis the layer of epidermis that secreted the gill wall and the layer that secreted the spiracular atrium are left behind in the lumen of the gill, together with blood, as the body wall epidermis retracts away from the pupal cuticle. A thin sheet of cuticle, the basal membrane, is secreted across the opening into the gill lumen at this time. The epidermis and blood in the gill lumen are thus completely isolated from the haemocoele of the living animal by the basal membrane, a layer of moulting fluid, and the adult cuticle. The tissue contained in the respiratory horns of terrestrial Dolichopodidae is isolated in a precisely similar manner.The tissue isolated in the lumen of the gill of Aphrosylus does not degenerate until after the pupal-adult ecdysis. It seems to be discarded because, on balance, its loss is less damaging than the cost that would be incurred in other ways by its absorption or retraction into the body of the adult. For instance, in order to absorb the tissue in such long appendages, or to retract all of the epidermis from within them, would necessarily prolong the moulting period, a period when the insect is particularly vulnerable.
The Tube-WormSpirorbis Vitreusand its Distribution in Britain
Authors: Crisp D. J. , Bailey Julie H. , Knight-Jones E. W. 
Published: May 2009

Spirorbis vitreus(Fab.), an arctic form, seems to be absent from Wales and most of England, but is generally abundant off the west coast of Scotland and also occurs in certain localities off Ireland, the Isle of Man, Cornwall and Brittany (which is probably its southern limit in Europe). Its range thus extends farthest down our western coasts, a distribution which is characteristic of various other northern and southern forms that are near the limits of their geographical ranges. Such species presumably benefit from the equable temperatures, adjoining deep water, and this winter-breeding species ofSpirorbisalso needs freedom from abrasion.The tubes of juvenileS. vitreusare very different from those of adults. The distribution of uncini on the abdomen shows a remarkable bilateral asymmetry, as inS. spirillum.
Observations on Kylinia Rosulata From S.W. England
Authors: Boney A. D. , White E. B. 
Published: May 2009

A description is given of the minute epiphytic red alga Kylinia rosulata Rosenv. from collections made in the Plymouth area, and from old herbarium material. The diagnostic characters of this and related species are discussed.The minute epiphytic red alga Kylinia rosulata (order Nemalionales, sub class Florideophycidae) was first described by Rosenvinge (1909) from dried specimens of Sporochnus pedunculatus (Huds.) Ag., collected from the Northern Kattegat. Kylinia was observed on the terminal assimilatory filaments of the supporting plant. Since the original description, this small plant has had a somewhat confused history from both the taxonomic and nomenclatural points of view. Feldmann(1963) has recently summarized the available data, and has verified the validity of the genus and species as originally described by Rosenvinge (see also Feldmann, 1958). K. rosulata is characterized by the possession of short prostrate filaments arising from a single attaching cell, each cell containing a parietal chromatophore, and with male plants bearing a hyaline hair-like body—called the ‘androphore’ by Rosenvinge (1909) and ‘spermatocystophore’ by Feldmann (1958).
Some Effects of Salinity on the Survival, Moulting, and Growth ofCorophium Volutator[Amphipoda]
Authors: Mclusky Donald S. 
Published: May 2009

An experimental study of the effects of salinity on the mud-dwelling amphipod,Corophium volutator(Pallas), indicates that, if supplied with mud, it will survive the salinity range of 2.50 %0, and without mud the range 7.5-47–5 %0. Moulting occurred in salinities of 2.6–46 %0, but most frequently in the range 5–20 %0. Growth occurred at a maximum rate in 15.4 %0, and only slightly slower at 4.4 and 30.6 %0; but below 4.4 %0the growth rate was progressively reduced. Freezing point studies showC, volutatorto be a hyperosmotic regulator, having a tissue tolerance range of 13–50 %0. The importance of a supply of mud, and the significance of hyperosmotic regulation are briefly discussed.INTRODUCTIONThe amphipodCorophium volutator(Pallas) is an inhabitant of littoral muds, the populations often reaching high densities. It has been most commonly reported from shores of estuaries, although Zenkevitch (1963) has stated that it may also occur in muds submerged to a depth of 10 m. Segerstråle (1959) has summarized the data available on the occurrence and distribution ofC. volutator. Since that date, work has been done on substrate selection (Meadows 1964a–c), on burrowing behaviour (Meadows & Reid, 1966) and on rhythmical swimming activity under tidal control (Morgan, 1965). Many authors (Nicol, 1935; Thamdrup, 1935; Beanland, 1940; Spooner & Moore, 1940; Rees, 1940; Goodhart, 1941; Stopford, 1951; Rullier, 1959; Gee, 1961) have described the substrate in whichC. volutatoroccurs. They have agreed thatC. volutatoris found in mud or muddy sand, containing approximately 37 % silt or clay.
On the Growth at Moulting of Lobsters (Homarus Vulgaris) in Cornwall and Yorkshire
Authors: Hepper B. T. 
Published: May 2009

In experiments in Cornwall and Yorkshire 214 marked lobsters (Homarus vulgarisM. Edw.) were returned after moulting. Of these a number had moulted more than once, and the separation into once-, twice- and three-times-moulted lobsters was achieved using probability paper.There was no significant difference in growth of lobsters from the two areas. It is concluded that the best method of plotting growth in lobsters is to plot carapace length before moulting against carapace length after moulting.It is concluded that male lobsters show arithmetic growth over the size range 68–123 mm carapace length, adding a constant mean increment of 9.8 mm carapace length at each moult.It is concluded that arithmetic growth, with a mean increment of 8.4 mm, adequately describes the growth of female lobsters over a small size range centred on a mean size of about 85 mm, but would lead to inaccuracies over a wider size range.The concept of arithmetic growth in relation to the general growth pattern is briefly discussed.IntroductionIn a population study a knowledge of the growth rate is essential. In crustaceans estimation of the growth rate is complicated by two factors: first, it is usually not possible to age the animals, and second, the growth rate is made up of two components, the increase in size at moulting and the frequency with which moults occur.The present paper presents data on the growth of lobsters at a moult, obtained from field experiments conducted in Cornwall in 1957–59, and in Yorkshire in 1958 and 1960.
A Seasonal Cycle in the Testis of the Spurdog, Squalus Acanthias, and the Sites of 3β-Hydroxysteroid Dehydrogenase Activity
Authors: Simpson T. H. , Wardle C. S. 
Published: May 2009

The histology of the spurdog (Squalus acanthias L.) testis was observed through a complete annual cycle. The maximum sperm accumulation coincided with the breeding time as defined by the biennial female cycle. Degeneration of spermatogonia was observed following breeding. The band of degenerate germinal ampullae was identical to that described as occurring in Scyliorhinus canicula (L.) following pituitary ventral lobectomy. This suggested a resting phase in the production of a specific pituitary gonadotrophin lasting for about four months. All spermatocytes were transformed to spermatozoa within 12 months. 3β-Hydroxysteroid dehydrogenase activity was located in semen, in Sertoli cell cytoplasm and in the lumens of mature germinal ampullae. A possible seasonal change in this activity due to the migration of the degenerate band is suggested. Interstitial cells of Leydig could not be observed.INTRODUCTIONThe Scottish-Norwegian stock of the spurdog, Squalus acanthias L., sampled for this study, was shown by Holden (1965) to make an autumn breeding migration from the region of the Orkney and Shetland isles to the breeding areas in the Minch off north-west Scotland. During January and February those females carrying embryos at the end of their second year of development move inshore and liberate their young in shallow water. At this time the ovaries of these fish contain from three to fifteen eggs ready for ovulation (Holden & Meadows, 1964), and observations suggest that copulation, ovulation and the commencement of a further pregnancy follow almost immediately. Following copulation, the spermatozoa must reach the oviducal gland at the head of the oviduct in order that the eggs may be fertilized before they are enclosed by the candle membranes.
Population structure of thornback rays Raja clavata and their movements in the Bay of Douarnenez
Authors: Rousset Jean 
Published: May 2009

The population structure of the thornback ray, Raja clavata L., expressed in terms of length and sex, seems to be related to hydrological conditions prevailing on the sampling areas. In the exposed area (Cove of Bertheaume), females are more frequently captured than males, and indeed represent the entire catch in the summer. In contrast, in the relatively sheltered area (Bay of Douarnenez) a majority of adult males and immature females are caught.After winter, only adults and juveniles of Raja clavata migrate into the Bay of Douarnenez. This bay may be a mating area for adults and also a nursery for juveniles particularly for immature females.
Depth related variation in the structure and functioning of the compound eye of the Norway lobster Nephrops norvegicus
Authors: Gaten E. , Shelton P.M.J. , Chapman C.J. , Shanks A.M. 
Published: May 2009

The mobility and quantity of retinula cell proximal screening pigment, and the liability of the eyes to light-induced damage, were investigated in the Norway lobster, Nephrops norvegicus (L.), obtained from three separate populations from depths of 18, 75, and 135 m.During the morning after capture, the migration of the proximal pigment in response to the onset of illumination below the threshold for damage varied between the three populations. In the eyes of deep water N. norvegicus, the proximal screening pigment was located close to or below the basement membrane when dark-adapted and rose to a position midway up the rhabdoms when light-adapted. In the dark-adapted N. norvegicus from shallow water the proximal pigment was located more distally than in eyes of deep water animals. After the onset of illumination, the pigment migrated distally to completely cover the rhabdoms. The amount of retinula cell proximal screening pigment was found to decrease linearly with depth.When dark-adapted individuals from each depth were exposed to light a positive correlation was obtained between the photon fluence rate (PER) and the proportion of the retina damaged. For a given light exposure the amount of damage was highest in animals from deeper water. The PFR causing 25% damage was approximately 1 log unit higher in animals from 18 m compared to those from 135 m.The amount of damage varied with the delay between capture of the animals and exposure to light. When exposed 2 h after capture significant differences between depths were seen but the results were influenced by the incomplete dark adaptation of some specimens.
A model of the relationship between light and primary production in an atoll lagoon
Authors: Charpy Loïc , Roubaud-Charpy Claude Julia 
Published: May 2009

The Tikehau atoll (Tuamoru Archipelago, French Polynesia) is located at 14°S 148°W. Phytoplankton and sand microalgae are the most important primary producers of the lagoon. They were studied for 4 years.The relationship between light energy and lagoonal primary production was measured by using the14C method for phytoplankton and O2method for phytobenthos. Incubations, carried outin situ, were made at different depths and light exposition times.Irradiance was high and 17% of the light energy measured at the surface reached 25 m (lagoon average depth). Maxima of phytoplankton and phytobenthos productions occurred at low depths; there was therefore no photoinhibition of photosynthesis. Correlations between light energy and primary production were strong, especially for phytobenthos. Multiplicative linear regression models (productionvslight) associated with an exponential linear regression model (lightvsdepth), allowed planktonic and benthic primary production to be predicted from the depth and the light energy received at the surface. The benthic primary production exceeded the phytoplanktonic production in the upper 18 m. The total primary production (benthos + plankton) was constant with depth and depended only on light energy at the surface. One Einstein received at the lagoon surface allowed the growth production of 14 mg of carbon (water column + sediments).
Winter warming in the southern Bay of Biscay and Lagrangian eddy kinematics from a deep-drogued Argos buoy
Authors: Pingree R. D. 
Published: May 2009

The winter of 1989/1990 was a year of marked warm water inflow along the Iberian, Spanish and French continental slopes and three anticyclonic eddies developed in the southern Bay of Biscay. Winter temperatures along the northern Spanish slope were examined in the belief that warm water inflow is related to the production of anticyclonic eddies in the southern Bay of Biscay. The annual cycle of temperature (at ~200 m depth) is most unusual in that the warmest temperatures occur in January, the coldest in the summer. Year-to-year variations are evident with the suggestion of a periodicity, though variable, of about five years.In April 1992, an opportunity presented itself for a late winter eddy survey in the south-eastern corner of the Bay of Biscay from RRS ‘Charles Darwin’. Two Argos buoys were deployed in what was thought to be, or would develop into, an anticyclonic eddy, and one of the buoys was caught in the eddy. This buoy was drogued at a depth of 320 m in a relatively well-mixed part of the water column thought to contain the eddy core. This buoy made ~60 clockwise orbits in the eddy and remained within 15 km of the eddy centre over the 200-d observation period. The normalized relative central vorticity of the eddy had a minimum value of -0·6 and the eddy rotation period experienced by the buoy ranged from 2·5 to 6·5 d. The decay scale for the eddy was estimated at 250 ±100 d. The mean variance of the east-west velocity component was significantly larger than the north-south value, and the buoy's orbit was significantly elliptical towards the end of the period of the observations.
Population parameters of Argentina sphyraena [Isospondyli] from west of Britain
Authors: Halliday R. G. 
Published: May 2009

IntroductionMonthly samples of Argentina sphyraena L. taken in the Clyde Sea Area over 2 years were used to describe age, growth, length-weight relationship, annual cycle in condition, and mortality. Results indicate that one transparent ring is laid down in the otoliths each year between November and May, providing a means of ageing this species.