bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experiments with Radioactive Strontium (90Sr) on Certain Molluscs and Polychaetes
Authors: Fretter Vera 
Published: May 2009

IfArion hortensisbe fed on a diet which contains 90Sr, autoradiographs show that the isotope istaken up by the digestive and lime cells of the digestive gland. From the former it passes to th haemocoel; in the lime cells it is concentrated around the calcium spherules. Some of the tracer enters the body through the wall of the intestine. Calcium stores which surround blood vessels and calcium cells in the mantle also concentrate the tracer.InAplysia.punctata90Sr from the surrounding water passes through the surface of the body, and especially the gill; inAcanthodoris pilosaions which enter the tissues from the sea water accumulate around the numerous calcium concretions in the mantle. These marine molluscs obtain cations directly from the water as well as by way of the food.There is a slow uptake of strontium ions by the ctenidia ofMytilus edulis, though, even in filtered sea water, the gut is the more important area for their ingress to the body. It is possible that they enter with the mucous feedingsheets. They pass readily into the cells of the digestive gland. Some of the isotope taken in with the food is absorbed by the wall of the intestine; this also occurs in Patella vulgata, in which the intestine provides a much larger area, and inLepidochitona cinereus.Mytilusplaced in filtered sea water which is activated with 90Sr, so increasing the strontium content by 007%, show the tracer localized for excretion within 10 hr. Ions are aggregated in the pericardial glands, not in the kidney.
Notes on the Medusa Amphinema Krampi Russell
Authors: Russell F. S. 
Published: May 2009

In a recent paper (Russell, 1956) I described a new medusa Amphinema krampi from a single specimen. I have now found three more specimens in collections made with a 2 m stramin ring trawl by R.V.Sarsia. Two of these were caught on 13 June 1956 at 48° 29' N., 9° 05' W. with 450 fathoms of wire out; one was a female 7 mm high and the other a male about 5 or 6 mm in height. The third specimen, a male 6·5 mm high, was taken on 4 July 1956 at 47' N., 5° 47' W. with 880 fathoms of wire out. Of the three specimens the female being the best preserved was kept intact; the two males were used for sectioning.It is now possible to add to my previous description of the species. As in the specimen already described, the umbrellas are crumpled and have their margins turned inwards. In the female, however, it is certain that there is a small apical projection. The radial canals leave the stomach below the lower limits of the gonads so that there are fairly long 'mesenteries'. The marginal tentaculae are six in number in each specimen, two perradial and four interradial. It is possible therefore that the eight which I recorded in my first specimen may have been an abtext-abstract number. The interradial female gonads are irregularly folded and much corrugated. All specimens have exactly the same coloration as that given in my previous description. A drawing of the female medusa is given in Fig.
Chemical changes in sea water off Plymouth during 1957
Authors: Armstrong F. A. J. , Butler E. I. 
Published: May 2009

Analyses of sea water collected during 1957 at the International Hydrographic Station E1 (lat. 50° 02′ N., long 4° 22′ W.) are given here in the same form as in earlier reports (Armstrong, 1954, 1955, I957> 1958). The methods of collection and of analysis for phosphorus and silicon are substantially unchanged. Some analyses were made for ammonia by a vacuum distillation method (Riley, 1953), and for inorganic nitrogen (nitrate + nitrite + ammonia) by reduction of nitrate and nitrite with nickel (Riley & Sinhaseni, 1957) to ammonia, which was vacuum distilled. Salinities were determined by the Government Chemist's Department.We wish to express our thanks to Lt.-Cdr. C. A. Hoodless and the crew of R.V. ‘Sarsia’ and to Capt. W. J. Creese and the crew of R.V. ‘Sula’, for assistance at sea.
Quantitative differences in the fauna of boreal mud associations
Authors: McIntyre A. D. 
Published: May 2009

SUMMARYThe fauna of a muddy area in the northern North Sea (the Fladen ground) is compared with that of a similar area in a Scottish west-coast sea loch (Loch Nevis). These areas were selected because certain similarities in environmental features and in fauna, coupled with their marked difference in biomass, make them particularly suitable for studies of the factors affecting benthic production.For macrobenthos samples (from a grab) a coarse sieve with round holes of 1-3 mm diameter and a fine sieve with meshes of 0-5 mm side were used. Meiobenthos samples (from a corer) were sieved through a 0124 mm mesh and the total residue stained in rose bengal.The Fladen ground, depth 140 m, had annual bottom temperatures between 6-31 and 8-22 C and salinities between 35-20 and 35-2.50. The deposit was mainly of coarse silt with abundant tests of small Foraminifera. The fauna is redescribed. The characteristic species was the foraminifer Saccammina sphaerica. By separating empty tests from living specimens it is shown that this species was not so abundant as had been thought. The main lamellibranch was Thyasira equalis, not T. flexuosa as recorded in previous work. Other important species were the polychaetes Paraonis gracilis, Myriochele heeri, Spiophanes kroyeri, Tharyx sp., Lumbrineris impatiens, and Nephthys incisa. The standing crop of macrobenthos was 6-42 g/m2 wet weight.
Biological differences between sea waters: experiments in 1960
Authors: Wilson Douglas P. , Armstrong F. A. J. 
Published: May 2009

SUMMARYSea water from the Plymouth district and sea water from the Firth of Clyde each produced, from the same batches of fertilized eggs of Echinus esculentus, a different morphological type of larva. Each type was clearly recognizable irrespective of the copper concentration up to a level higher than that ever likely to be found naturally in the localities from which sea waters contrasted in earlier experiments had been obtained. Suggestions by continental workers that these earlier results may have been due to varying copper concentration are thus shown to be inapplicable.
The use of thin-layer chromatography for the separation and identification of phytoplankton pigments
Authors: Riley J. P. , Wilson T. R. S. 
Published: May 2009

Thin-layer chromatography has been used for the rapid separation of microgram amounts of pigments of marine phytoplankton, both from cultures and from the sea. The separation is carried out on plates coated with silica gel; the chromatogram is developed with a solvent consisting of petroleum ether (b.p. 60–80°), ethyl acetate and diethylamine in the ratio 58:30:12 by volume. The separated individual pigments may be eluted from the plate and characterized by their absorption spectra. The pigments of the following phytoplankton have been examined: Dunaliella primolecta, Phaeodactylum tricornutum, Isochrysis galbana, Dicrateria inornata, Coccolithus huxleyi, and Peridinium trochoidium.IntroductionA knowledge of the component pigments of phytoplankton is of value in the systematic classification of these organisms and in the study of the mechanism of photosynthesis. Very little is known about the amounts of the lesser phyto-plankton pigments associated with the natural phytoplankton crop in the sea, but a considerable amount of work has been carried out on the measurement of chlorophylls a, b and c and of carotenoids for the estimation of the plant bio-mass in the sea. These determinations are usually carried out by modifications of the poly-chromatic spectrophotometric method originally described by Richards with Thompson (1952) and modified by Creitz & Richards (1955) (see also Parsons & Strickland, 1963). While these procedures give a satisfactory measure of chlorophylls a and b, their precision for chlorophyll c and carotenoids is poor; furthermore, no resolution of carotenes from xanthophylls can be attained; nor can any indication of the presence of unusual pigments be obtained.
The larvae of some monogenetic trematode parasites of Plymouth fishes
Authors: Llewellyn J. 
Published: May 2009

Techniques for the rearing of monogenean larvae are described.The new term ‘oncomiracidium’ is proposed for the larvae of monogenetic trematodes.Eleven new oncomiracidia offish parasites are described, bringing the total now known to thirty-five.These oncomiracidia are tentatively classified, and the classification is compared with the existing classification of adult monogeneans.
On the Nutrition and Metabolism of Zooplankton X. Quantitative Aspects ofCalanus HelgolandicusFeeding as a Carnivore
Authors: Corner E. D. S. , Head R. N. , Lindapennycuick C. C. Kilvington 
Published: May 2009

INTRODUCTIONIn an earlier study (Corneret al.1974) the copepodCalanus helgolandicus(Claus) was found to feed actively on nauplii of the barnacleElminius modestusDarwin, one adult female ingesting a maximum daily ration equivalent to 25% of the body nitrogen. The present work, in whichElminiusnauplii have again been used as a diet, extends the earlier study by determining how efficientlyCalanusdigests an animal food. In addition, the methods used have provided information on other aspects of carnivorous feeding byCalanus, including the relationship between food concentration and size of ration ingested as well as gross growth efficiency, i.e. the proportion of ingested food invested in growth.
Comparison of the Temperature Responses of Barnacles From Britain, South Africa and New Zealand, With Special Reference to Temperature Acclimation In Elminius Modestus
Authors: Ritz D. A. , Foster B. A. 
Published: May 2009

IntroductionThe importance of temperature in limiting the distribution of marine invertebrates by its effects on breeding and survival has been shown by Orton (1920) and Hutchins (1947). Prosser (1955) recognized the use of physiological variation in describing interspecific relations, intraspecific variation and the limits of ecological range. The effects of temperature on marine organisms have been reviewed by Kinne (1963). Temperature responses are to a certain extent genetically fixed and species characteristic, although it is well known that many species can adjust these responses with changing temperatures.
Morphogenesis of the Hinge in the Larva and Postlarva of the Brackish-Water Cockle, Cerastoderma Glaucum
Authors: Pennec Marcel Le , Yankson Kobina 
Published: May 2009

IntroductionThe morphology of the Cardiidae is extremely variable and their taxonomy is uncertain because of the difficulty in recognizing the differences that are genetic and the variations that are due to environmental conditions. This is the reason why Cerastoderma glaucum (Bruguière) (Fig. 1) and C. edule have been for a long time considered as ecotypes of one species or two taxons belonging to a super-species C. edule (Lubet, 1976).
A Note on the status of Rhabdopleura From Bermuda
Authors: Dilly P. N. 
Published: May 2009

INTRODUCTIONG. O. Sars found the first specimens of Rhabdopleura in 1866. The specimens were found by dredging at 220 m at Skraaven in the Lofoten Islands. However, the first Rhabdopleura was described by Allman in 1869 (a, b, c) which he called Rhabdopleura normani in honour of A. M. Norman who together with J. G. Jefferys found them while dredging at 165 m off the Shetland Islands in 1868.
Aspects of Gametogenesis in the Marine Mussel Mytilus Edulis L.
Authors: Lowe D. M. , Moore M. N. , Bayne B. L. 
Published: May 2009

INTRODUCTIONMarine bivalve molluscs have in recent years attracted considerable attention for a variety of reasons, not least of which is their importance as a source of food for man. Much of this research has concentrated on studies of reproduction; Mytilus viridis (India: Nagabhushanam & Mane, 1975), M. edulis aoteanus and Aulacomya maoriana (New Zealand: Kennedy, 1977);Choromytilus meridionalis and Aulacomya ater (South Africa: Berry, 1978); Mytilus (= Perna) perna (Brazil: Lunetta, 1969); M. edulis planulatus (Australia: Wilson & Hodgkin, 1967); Mytilus californianus and M. edulis (U.S.A.: Hines, 1979); Mytilus galloprovincialis (France: Lubet, 1959) and M. edulis (U.K.: Chipperfield, 1953; Seed, 1975; Bayne et al. 1978). A review of the literature revealed that in the majority of studies cytology was used as a descriptive tool for the ‘staging’ (Chipperfield, 1953; Lubet, 1957; Seed, 1975, 1976) of the developing gametes and certain anomalies were apparent with regard to the nomenclature of the connective tissue matrix of the mantle lobes.
Food And Feeding Habits Of Raja Species (Batoidei) In Carmarthen Bay, Bristol Channel
Authors: Ajayi T. O. 
Published: May 2009

INTRODUCTIONThe food and feeding habits of rays (genus Raja) have received more attention than other aspects of their biology. Being nocturnal feeders (Bigelow & Schroeder, 1953), they have been thought to locate food by smell rather than by sight (Steven, 1930, 1947). More recently, the ability of the electric receptors to detect even weak action potentials has been linked with food foraging (Kalmijn, 1966). Wilson (1953) observed that the behaviour of Raja while apprehending prey was similar to that of Torpedo spp. The functional advantages of a ventral mouth as an adaptation to bottom feeding have been stressed by Alexander (1970).Day (1880–1884) recorded that rays ate molluscs, crustaceans and fish. That the young of Raja clavata, R. montagui (as R. maculata), R. naevus and R. brachyura feed on crustaceans was observed by Clark (1922). Steven (1930, 1932, 1947) confirmed this in a wider age sample of the same species, adding that juveniles which ate amphipods and crangonids later changed to Upogebia, Portunus and Corystes cassivelaunus, whereas the adults were highly piscivorous and sometimes cannibalistic. Both Clark and Steven obtained their fish close to Plymouth. Lazzareto (1964) and du Buit (1969), largely corroborating the above, included polychaetes in the list of food items but specified no differentiation according to size.Holden & Tucker (1974), recording only presence or absence of food items, studied R. clavata, R. brachyura, R. montagui and R. naevus from a much wider area.
Petroleum compounds in the marine food web: short-term experiments on the fate of naphthalene in Calanus
Authors: Corner E. D. S. , Harris R. P. , Kilvington C. C. , O'Hara S. C. M. 
Published: May 2009

Adult female Calanus helgolandicus Claus immersed for 24 h in sea-water solutions of [1-14C]naphthalene accumulated a detectable quantity (3.6 pg/animal) from concentrations as low as 0.10 μg/1.Feeding experiments using barnacle nauplii or diatoms as foods showed that the dietary route of entry was more important quantitatively than direct uptake from solution in that in order to ensure that the same quantity of radioactivity in the animals was attained by the two routes the level of hydrocarbon in solution had always to be far greater than that present as paniculate food. Relevant to these observations was the further finding that after naphthalene had been accumulated directly from solution in sea water depuration was rapid and only a small fraction, less than 5%, of the original radioactivity could be detected after 10 days: by contrast, when the hydrocarbon was taken up by way of the food depuration was much slower, so that at the end of 10 days about a third of the original level of radioactivity still remained in the animals. Short-term experiments in which Calanus were fed on labelled diets for 24 h under bacteria-free conditions showed that at the end of this period over 90% of the radioactivity in the animals was present as unchanged naphthalene. However, more than two thirds of that released by the animals was in some form other than the hydrocarbon, a finding consistent with the view that Calanus is able to metabolize it.
New British species of Doto Oken, 1815 (Mollusca: Opisthobranchia)
Authors: Lemche Henning 
Published: May 2009

INTRODUCTIONDuring the last 25 years I have collected opisthobranchs from more than 1200 stations (dredgings, collecting by divers, visits on the tides etc.) all around the Northern Atlantic, and among them close to 200 from the British Isles, viz. during two short visits to Plymouth, two somewhat longer ones to Menai Straits, one to Millport in Scotland, and three to Carna in W. Eire. In all those places, the respective marine stations, leaders and personnel, have been of the utmost help and assistance, and I hereby express my warmest appreciation for the kind way in which I have been received. Without that strong support I should never have been able to accomplish the task of comparing live specimens of opisthobranchs from all around the Northern Atlantic in order to tackle all the taxonomic problems involved. The present paper on the genus Doto is my first separate contribution to a revision of the British nudibranchs. The material obtained is kept in the Zoological Museum of the University of Copenhagen.
Frontal Horns and Associated Gland Cells of the Nauplii of the Barnacles, Balanus Hameri, Balanus Balanoides and Elminius Modestus (Crustacea:Cirripedia)
Authors: Walker G. 
Published: May 2009

Frontal horns are prominent structures, characteristic of the nauplii of most cirripedes. Such horns are more prominent amongst the Lepadomorpha, i.e. Lepas (see Groom, 1894).Reference is made to frontal horns in those papers concerned with the identification of nauplii (Nilsson-Cantell, 1921; Herz, 1933; Bassindale, 1936; Batham, 1946; Pyefinch, 1948; Buchholz, 1951; Barnes and Barnes, 1959a, b), but more detailed descriptions of horns and associated gland cells are limited to the studies of Groom (1894), Kaufmann (1965) and Walley (1969).In the present study, the morphology of the frontal horns and the cytology of associated frontal horn gland cells of three barnacle species - Balanus hameri (Ascanius), Balanus balanoides (L.) and Elminius modestus Darwin were investigated.
Muscle Proteins of the CoelacanthLatimeria ChalumnaeSmith
Authors: Hamoir G. , Piront A. , Gerday Ch. , Dando P. R. 
Published: May 2009

Although the anatomy of the coelacanth muscles has been examined very thoroughly, their protein composition has, until recently, not been investigated. Thanks, however, to the 1972 British–French–American expedition to the Comores, frozen material has been made available and some results on myoglobin and four glycolytic enzymes have already been published. We have carried out a comparison of the sarcoplasmic proteins of red and white muscle by starch-gel electrophoresis. The ninhydrin-positive dialysable constituents and the myofibrillar proteins of white muscle have also been examined.A few puzzling results obtained with the white muscle extracts have been related to the occurrence of o.1 M ammonia, due presumably to the splitting of urea by a bacterial urease, and to an alteration of the active thiol groups of GAPDH and PK. If due account is taken of these unusual post-mortem changes, the extractability of the proteins and their properties are strikingly similar to those of teleosteans. The comparison of the sarcoplasmic proteins of white and red muscle by starch-gel electrophoresis revealed also that the differentiation observed in the coelacanth was similar to that occurring in the carp. A study of the low-molecular-weight proteins, or parvalbumins, of white muscle and of the myofibrillar proteins also shows the expected differences between the two muscle types.The only abnormal features observed in this study were the high concentration of parvalbumins, 1.5–2 times that found in other species examined, and the occurrence of an unusual globulin fraction which was easily extracted at ionic strength 0.5 and insoluble at ionic strength 0.35 and neutral pH.
The Larva of a Didemnid Ascidian, with Notes on the Structure of the Colony and the Adult
Authors: Millar R. H. 
Published: May 2009

There are few adequate descriptions of British members of the ascidian family Didemnidae and little attention has been given to the larvae. In the autumn of 1947 a didemnid was collected from the intertidal zone in the Menai Strait, North Wales. This ascidian agrees superficially with Leptoclinum maculosum Edwards, as figured by Milne Edwards (1842) and by Alder & Hancock (1905–1912), although differing somewhat from the diagnosis of Didemnum maculosum (Edwards) given by Harant & Vernières (1933). It is closer anatomically to the D.fulgens (Edwards) of Harant & Vernières, but differs in colour. In most features the colony and zooid closely resemble the descriptions given by Michaelsen (1923) for his species D. helgolandicum Michaelsen, and it is probable that this is the species to which it should be assigned. Nevertheless, the name D. maculosum has been retained since it is under that name that it has probably appeared in most faunistic lists.Until recently all accounts of didemnid larvae have described three anterior adhesive organs. This was the number given by Giard (1872) for Diplosoma gelatinosum Edwards, and by Lahille (1890) for Trididemnum tenerum Verrill and Polysyncraton lacazei Giard. Berrill (1947), however, has described a new species of didemnid, Trididemnum alleni Berrill, the larva of which has only two anterior adhesive organs, a condition not previously found in any ascidian larva.The larva (Fig. IA) of the colonies found in the Menai Strait resembles that of T. alleni in many features. The trunk is about 0.35 mm. long from the tip of the adhesive organs to the base of the tail.
Correlation of Some of the Physical and Chemical Properties of the Sea With the Chemical Constitution of the Algae
Authors: Black W. A. P. , Dewar E. T. 
Published: May 2009

Monthly samples of the Laminariaceae, L. saccharina and L. cloustoni, from three localities on the Argyllshire coast have been taken from March 1948 to March 1949, and analysed for dry matter, ash, mannitol, laminarin, crude proteins, inorganic nitrogen and alginic acid, and the seasonal variation in these constituents correlated with the changes in composition of the sea water.The results show that a correlation does exist and that a period of rapid photosynthesis occurs from March to June/July, but is restricted in July/August when nitrate is undetectable in the water and phosphate is as low as 0·16–0–20 mg. atom/m.3. The replenishment of the photosynthetic layer with nutrients is retarded in July/August, apparently due to the warming of the inshore waters, which may set up a thermocline restricting vertical mixing.The autumn cooling of the uppermost waters facilitates vertical mixing, regenerating the nutrients in the photosynthetic region, and a second burst of photosynthesis at a reduced rate from the spring ‘outburst’ occurs in October/November.
The Growth Rate Of Verruca Stroemia (O. Müller)
Authors: Barnes H. 
Published: May 2009

Data are presented on the growth rate of Verruca stroemia under natural conditions and when exposed continuously and cleaned repeatedly. Several series exposed at different times of the year were followed.Rapid growth takes place (under raft conditions) following settlement; the maximum size is virtually reached in one season's growth between spring and early winter. There is little growth in midwinter.Differences between the mean specific growth rates of the various series can be ascribed to differences in the availability of food.The question is discussed as to whether there is any seasonal rhythm; the evidence indicates that no marked rhythmic pattern of growth exists.Observations on deep-water populations would be of value for comparison and to unmask any relatively weak rhythmic growth.The mean specific growth rates at half their maximum size are compared for several species—Balanus balanoides, B. crenatus, B. balanus, Chthamalus stellatus and Verruca stroemia; it is similar for all species except Chthamalus stellatus. The high level barnacle may require stimulation such as is provided by wave action to elicit full metabolic activity.