bluuebunny/crossref_metadata_2025_split huggingface dataset:
The rapid response ofMyxicola infundibulum(Grübe)
Authors: Roberts M. B. V. 
Published: May 2009

In Myxicola the rapid muscular response produced by direct stimulation of the nerve cord with a single shock is usually large and obeys a simple ‘all-or-nothing’ relationship to the intensity of stimulation. A single shock of sufficient strength evokes a single giant fibre impulse which produces an extensive contraction of the longitudinal muscle.The magnitude of the summated contraction obtained by repetitive stimulation of the nerve cord is found to depend on the number and frequency of the shocks, thus providing the animal with a mechanism by which, theoretically, it could grade its escape response.
The reactions of certain mysids to stimulation by light and gravity
Authors: Foxon G. E. H. 
Published: May 2009

Light-adapted mysids as exemplified byHemimysis lamornaedisplay phototelotaxis which regularly alternates in sign from positive to negative andvice versa. This reaction may be disturbed by other activities such as feeding; it only takes place in horizontal illumination.Dark-adapted mysids display negative geotaxis. When a light stimulus is given this geotaxis is reversed in sign irrespective of the direction of the incident light.When the statocysts of the mysids are removed their responses are much more like those of planktonic creatures. In the light normal orientation is maintained by the “dorsal light reflex”, and in darkness by the “general position reflex”. In the darkness a feeble negative geotaxis is sometimes seen. In light, phototaxis is seen in both light-adapted and dark-adapted conditions; in the majority of cases it is negative but on occasion has been seen to be positive.
Studies on Marine Flagellates
Authors: Parke Mary 
Published: May 2009

Six marine flagellates, used as food in the rearing of the larvae ofOstrea edulisL., are described.One belongs to the Chlorophyceae,Pyramimonas grossiin.sp. (Polyblepharidaceae); four belong to the Chrysophyceae,Chromulina pleiadesn.sp. (Chromulinaceae),Isochrysis galbanan.g., n.sp.,Dicrateria inornatan.g., n.sp.,D. gilvan.g., n.sp. (Isochrysidaceae); and one belongs to the Cryptophyceae,Hemiselmis rufescensn.g., n.sp. (Nephroselmidaceae).A form of reproduction in a palmelloid phase, not previously described, is recorded for the Isochrysidaceae.
Regeneration in the polychæt Chætopterus variopedatus
Authors: Berrill N. J. 
Published: May 2009

1. Regeneration from different levels in the polychæt worm Chætopterus variopedatus has been studied.2. Regeneration can occur posteriorly from any segment, but anteriorly only from segment XIV forwards.3. Where regeneration occurs at all, given sufficient time, it will be complete, i.e. the original segments occupy in the new worm the relative position they originally occupied in the old worm.
The Ascidian Fauna of the Plymouth Area
Authors: Berrill N. J. 
Published: May 2009

The nomenclature followed is that used by Hartmeyer (9), in which account will be found identificattion keys and complete lists of the synonymous species, only the commoner of which are given below. That his conclusions in this respect are open to question has already been pointed out (see Journ. Mar. Biol. Assoc., Vol. XV, p. 159).For a description with figure of a species the reference number is placed after the name.
The Rapid Estimation of the Copper Content of Sea-water
Authors: Atkins W. R. G. 
Published: May 2009

1. The copper content of sea and river waters can be rapidly determined using the sodium diethyl-dithiocarbamate method followed by extraction with chloroform.2. This solvent takes up only traces of the natural colouring matters found in waters, but blank estimations should be made with some river waters and occasionally with sea-waters on account of the presence of plankton.3. Carbon tetrachloride can be used instead of chloroform as solvent, it extracts less per unit volume, but the volume recovered is larger, the resultant yield being identical. Amyl alcohol extracts more than chloroform, but the volume recovered is smaller, the resultant yield being about 0-8 times that of the others. The alcohol takes up more colouring matter from river water, does not separate as readily as the others, and floats, whereas they, more conveniently, sink. For work in hot climates its higher boiling-point may be an advantage.4. In fresh water iron salts in large excess might cause error; this can be checked by the electro-deposition method.
The suspended matter of sea water
Authors: Armstrong F. A. J. , Atkins W. R. G. 
Published: May 2009

Sea water collected at Station E1, surface, between June 1948, and November 1949, contained suspended matter from 2·77 to 0·45 g./m.3 (or parts per million) dried and ignited. A few determinations of insoluble organic matter gave 1·77 to 1·15 parts per million dry weight at 100° C. The ignited residue contained from 55 to 17% silica, 28 to 3 of ferric oxide, 20 to under 1 of alumina and 70 (or excluding one high value 29) to 9 calcium carbonate. There was nothing in the records for temperature or salinity to suggest that the water mass had changed during the period of sampling.The analyses reveal an unsuspectedly large amount of iron, compared with that found in solution. The ignited residue is rich in silicate, judging from the silica alumina ratio, but it is quite doubtful whether the additional supply of silicate available for diatoms is at all adequate to balance their requirements calculated on a phosphate utilization basis. It seems more probable that a considerable amount of the phosphate is available for non-siliceous phytoplankton.
The association of amphipods in the shallow-water sand habitat of Strangford Lough, Co. Down
Authors: Fincham A. A. 
Published: May 2009

Ten stations were sampled in the shallow-water sand habitat of Strangford Lough using a naturalist's dredge. Sediment samples were analysed to determine median diameter (ranging from 1·13 to 3·23 ø), Phi quartile deviation (ranging from 0·17 to 0·65 ø) and Phi quartile skewness (ranging from –0·11 to –0·04 ø).Twenty-two species of amphipod belonging to thirteen families were identified; ten species were new records for Strangford Lough and the Family Phoxocephalidae was recorded for the first time. The average number of species per station was nine and average abundance was 660 amphipods per station. The most frequently occurring species was the caprellid Phtisica marina (present in 90% of the samples); the overall dominant species was the corophiid Corophium crassicorne representing 52% of all specimens recorded.
The occurrence and seasonal variation of trace metals in the scallopspecten maximus(L.) andchlamys opercularis(L.)
Authors: Bryan G. W. 
Published: May 2009

A comparison has been made between the concentrations of eleven trace metals in the tissues of two species of scallops,Pecten maximus(L.) andChlamys opercularis(L.), collected from the same area of the English Channel. Although there was considerable variation between individual animals, the mean concentrations of Ag, Co, Cr, Cu, Mn, Ni, Pb and Zn were higher in the whole body ofChlamysthan inPectenbut concentrations of Al, Cd and Fe were lower. In both species, seasonal changes in the concentrations of Co, Cu, Fe, Mn, Ni, Pb and Zn were observed and, in general, the highest values were found in the autumn and winter months. These changes may be related to food supply, since concentrations were generally highest when phytoplankton productivity was low and tended to fall in the spring as productivity increased rapidly to its annual peak. Despite problems arising from individual and seasonal variation, the kidneys and digestive gland of scallops appear to have potential as biological indicators of trace metals.The results obtained forPectenandChlamysare compared with those in the literature for species from the family Pectinidae.
The calls of gadoid fish
Authors: Hawkins A. D. , Rasmussen Knud Just 
Published: May 2009

Of nine northern European species of the Gadidae examined in the aquarium, or in cages in the sea, four produced sounds. The vocal species were the haddock,Melanogrammus aeglefinus(L.); the cod,Gadus morhuaL.; the lythe,Pollachius pollachius(L.); and the tadpole-fish,Raniceps raninns(L.). The main differences between the calls of the vocal species lay in their temporal structure, all the calls being divisible into brief pulses of low frequency sound, repeated at different rates and in different groupings. Calls with this structure yielded spectra with a series of spaced harmonics, the frequency spacing depending upon the pulse repetition rate.Sixteen additional species were dissected, and seven of these showed well developed muscles attached to the swimbladder, similar to those found in the four vocal species. The remaining nine species, together with the five non-vocal species examined in the aquarium, lacked the muscles.The behavioural significance of the calls and the operation of the sound producing mechanism are discussed.
The taxonomic relationship of Parathemisto gaudichaudi (Guerin) and P. gracilipes (Norman), with a key to the genus Parathemisto
Authors: Sheader M. , Evans F. 
Published: May 2009

The results of morphometric and developmental studies made to elucidate the relationship between Parathemisto gaudichaudi (Guerin) and P. gracilipes (Norman) show them to be one and the same species. Apparent differences are due to differences in the size of specimens at maturity, and to the degree of development of the bispinosa-compressa condition. P. gaudichaudi takes precedence over P. gracilipes.The species is highly variable, existing in two extreme forms, the bispinosa form and the compressa form, together with all possible intermediates. The full range of the bispinosa-compressa condition is not expressed until a body-length of 10 mm is reached. Specimens are capable of changing towards either extreme at moults, but the factors causing the change are unknown.A key to the genus Parathemisto Boeck is included.
The feeding preferences ofAeolidia papillosa(L.) (Mollusca, Nudibranchia)
Authors: Edmunds M. , Potts G. W. , Swinfen R. C. , Waters V. L. 
Published: May 2009

A clear preference for the actinian anemonesActinia equina, Anemonia sulcataandAnthopleura elegantissimawas demonstrated, while the acontian anemones andCorynactis viridisranked low in the order of preference. The significance of acontia as defensive structures in anemones is discussed briefly. No differences in food preference were found between eolids collected from Plymouth and Millport; and BritishAeolidiabehaved in the same way towards Californian anemones as did CalifornianAeolidia.The eolids varied in their tendency to bite different species of anemone, but the performance of each individual eolid was similar in different experiments. It is possible that the individual variations may account for conflicting reports in the literature.
The Vertical Distribution of Marine Macroplankton. V. The Distribution of Animals Caught in the Ring-trawl in the Daytime in the Plymouth Area
Authors: Russell F. S. 
Published: May 2009

1. The vertical distribution of many species in daylight in the Plymouth area is shown, as a result of the examination of a number of serial hauls taken with the stramin ring-trawl between the dates April 2nd and August 6th, 1926.2. It is shown that probably the errors introduced by the employment of a non-closing net are for the present purpose negligible.3. The indications are that most species have an optimum level at which they live, in the daytime, the actual depth varying from day to day according to weather and other conditions.4. A few species appear to show no preference, being present equally abundantly at all depths or showing marked changes in the region of greatest abundance from day to day.5. A provisional list is given on page 567, showing the order in which many of the different species appear in greatest abundance from the surface downwards.6. The vertical distribution appears to differ for the two sexes of Calanus finmarchicus, the males tending to avoid the surface layers more than the females.7. The presence of the medusa Cosmetira pilosella in fair numbers in a catch in the daytime in the Plymouth region would seem to be a reliable indication that the net has been fishing below 20 metres.8. A catch of Calanus finmarchicus made by the stramin ring-trawl consists nearly always of over 80 per cent adults.9. No attempt has been made definitely to correlate behaviour with external factors: more observations are to be desired.10. Brief notes are given on the seasonal distribution of various species. The danger of drawing conclusions about seasonal abundance from daylight hauls only is shown by the results for Tomopteris helgolandica (p. 575).
The Phosphorus and Arsenic Compounds of Sea-Water
Authors: Atkins W. R. G. , Wilson Edith G. 
Published: May 2009

1. Much of what was formerly considered to be phosphorus in organic combination, in sea-water, is in reality arsenic.2. Certain analyses giving high values for phosphate in sea-water and a June minimum very far from complete exhaustion of phosphate are vitiated by the inclusion of arsenate, as arsenomolybdate, in the phosphomolybdate precipitate.3. Arsenic in sea-water exists mainly in the form of arsenite. The arsenate present, if any, has hitherto been included in the results obtained for phosphate.4. Since arsenic is found in algæ and has been recorded as increasing in quantity with increase of depth it seems that the arsenic present in sea-water must undergo seasonal changes.
Monitoring the Vertical Movements and Light Responses of Herring and Plaice Larvae
Authors: Blaxter J. H. S. 
Published: May 2009

The movements of herring and plaice larvae of different age, from hatching to about 8 weeks old, were monitored at different levels in a vertical tube by means of matched pairs of thermistors controlled and ‘balanced’ by bridge circuits. Movement of larvae past the thermistors upset the balance and the resulting change in the circuit could be followed on a pen-recorder. Having established, by visual comparisons, the interpretation of the pen record, experiments could be performed over extended periods or at low light intensities when visual observations would have been tedious or impossible. The numbers of larvae present were shown by the number of spikes on the pen record per unit time, while a measure of their size or activity was given by the height of the spikes.The light intensity could be altered by interposing neutral-density filters between an artificial light source and the surface of the tube. Alternatively, natural daylight could be beamed in by a mirror above the tube when placed by a window. Using artificial light, changes of very large intensity had little effect on the larvae until a critical level was reached (equivalent to the intensity at late dusk or early dawn) when a vertical migration took place. A similar vertical migration took place when the natural light at dusk was beamed in; many larvae then moved to the surface and remained there, apparently very active throughout the night untill the light increased at dawn. Vertical migration could be simulated in the laboratory at any time by imposing an artificial light-cycle of appropriate amplitude on the larvae.
Seasonal Changes in the Organic Forms of Carbon, Nitrogen and Phosphorus in Sea Water at E1 in the English Channel During 1968
Authors: Banoub M. W. , Williams P. J. leB. 
Published: May 2009

A seasonal survey of particulate and dissolved organic material was made at E1 in the English Channel during 1968. The average integral mean values were: dissolved organic carbon 65 μg-at C/l (780 μg C/l); dissolved organic nitrogen 4·6 μg-at N/l (64 μg N/l); dissolved organic phosphorus 0·12 μg-at P/l (3·8 μg P/l); particulate organic carbon 190 μg C/l and particulate organic nitrogen 21 μg N/l. Dissolved organic carbon and the particulate organic carbon and nitrogen showed increases subsequent to the spring bloom; such increases were less evident in the dissolved organic nitrogen results and not apparent in those of dissolved organic phosphorus.Analyses were also made in March and June in 1969 at two other stations in the English Channel, in addition to E1. The results from the three stations were basically similar.
A Red Tide of Gyrod Inium Aurelum in Sea Lochs of the Firth of Clyde and Associated Mortality of Pond-Reared Salmon
Authors: Jones K. J. , Ayres P. , Bullock A. M. , Roberts R. J. , Tett P. 
Published: May 2009

Red tides of the naked dinoflagellate Gyrodinium aureolum Hulburt occurred in sealochs in the north of the Firth of Clyde, Scotland, during late September 1980. Greatestconcentrations of the organism were found in the top 1 m layer of the water column, which was stabilized, and probably also enriched with nutrients, by freshwater input fromland drainage. In addition vertical and horizontal concentration must be postulated toexplain Gyrodinium cell densities of 2 x to7 cells I"1 and chlorophyll concentrations of 2228 mg m“”3 near the shore at Otter Ferry, Loch Fyne.On 28 September 1980, water containing the red tide at Otter Ferry was unintentionally pumped into fish ponds at a shore-based salmon farm and resulted in the death, in one pond, of 3000 salmon each weighing about 1 kg and of 200–300 smolts in another when water was transferred to it from the affected pond. Pathological investigation of affected salmon showed that death was likely to have resulted from asphyxiation and osmotic shock as a result of extensive cellular damage to gills and guts. Results of mouse bioassays, using acidic and ether extracts of flesh and guts from affected salmon, suggest that necrotizing toxin(s) was associated with the cells of Gyrodinium aureolum during the bloom. The clinical signs exhibited by mice injected with toxin extracts were, however, unlike those caused by paralytic shellfish poison or toxins of the Gymnodinium breve type.
Horizontal And Vertical Dencity Distribution of Platfarm and Cirripede Larvae Over an Inshore Rock Platform Off Northumberland
Authors: Wilson Stephen R. 
Published: May 2009

A fixed bottom net was used to study the relationship between the horizontal and vertical density distribution of polychaete and cirripede larvae over an inshore rock platform.Strong horizontal density distributions were obtained close to the bottom in many species from both groups, while the vertical samples showed larvae to be distributed towards the bottom both during the day and at night. It is suggested that the concentration of larvae within the slow-moving bottom water was responsible for the observed limited lateral larval dispersal.The results are discussed in relation to their bearing upon a number of problems within the field of meroplanktonic ecology.
Presidential Address
Authors: Firth C. H. 
Published: May 2009

When I remembered that I had to address the Society to-day I thought at first of choosing some subject remote from the troubles of the moment, something analogous to my former addresses on the development of historical studies in England. But it was not possible to do so. The events which are in progress now have too absorbing an interest to permit us to abstract ourselves from them, for which of us is not in some way or other intimately affected by them? Besides that, these events have for any historian not merely the interest which all of us share, but an interest of a very special kind. The historian sees in action before his eyes the abstractions he has been reading about in books all his life: the struggle of races, the conflict of opposing ideas, the operation of economic laws, the development of historical tendencies, and perceives what these phrases really mean when they are translated into facts. There has been no such open conflict of ideals since the wars of the French Revolution. There has been no such huge conflict of races since the time when the Teutonic peoples moved westward to overthrow Roman civilisation and plant their own in its place. One of Milton's similes for the Satanic host pictures their coming:‘A multitude like which the populous North Poured never from her frozen loins to pass Rhene or the Danaw, when her barbarous sons Came like a deluge on the South, and spread Beneath Gibraltar to the Libyan sands.’
Cryptosporidiosis from a community swimming pool: outbreak investigation and follow-up study
Authors: BOEHMER T. K. , ALDEN N. B. , GHOSH T. S. , VOGT R. L. 
Published: May 2009

SUMMARYTri-County Health Department investigated an outbreak of cryptosporidiosis linked to a community swimming pool. A cohort study was conducted in 37 persons who were invited to the pool party; 12 (57%) of 21 attendees had primary cryptosporidiosis infection. Risk factors for illness included swimming, getting water in mouth, and swallowing water. The pool met chlorination guidelines and used UV light irradiation, a supplemental disinfection technology that inactivatesCryptosporidium. A follow-up survey of the cohort was completed 7–8 weeks after the pool party; four (25%) of 16 non-attendees had secondary cryptosporidiosis infection. The median duration of illness, including patients with recurring symptoms, was 26 days. Clinical response rate to nitazoxanide, a therapeutic agent, was 67%. This study is unique because it describes a cryptosporidiosis outbreak from a well-maintained community swimming pool using supplemental disinfection. It also reports information on disease burden and treatment response.
n-3 Fatty acid intake from marine food products among Quebecers: comparison to worldwide recommendations
Authors: Lucas Michel , Asselin Geneviève , Plourde Mélanie , Cunnane Stephen C , Dewailly Éric , Dodin Sylvie 
Published: May 2009

AbstractObjectiveTo quantify marine food product consumption and EPA + DHA intake among Quebecers, and to compare the results with the most recent recommendations.DesignData were obtained from a representative cross-sectional telephone survey (June 2006). Intakes of marine food product species and EPA + DHA were estimated from a validated FFQ on the consumption of marine food products during the previous month. Prevalence of fish oil consumption in the last 6 months was also assessed.SettingProvince of Quebec (Canada).SubjectsA representative sample (n 1001) of adults in the province of Quebec. Of these, eight were excluded from the present analysis (n 993).ResultsMean and median EPA + DHA intakes for all participants were estimated to be 291 mg/d (sem 11) and 207 mg/d, respectively. 85·0 % (95 % CI 82·7, 87·3) of Quebecers had an EPA + DHA intake lower than 500 mg/d, which is the amount internationally recommended for the prevention of CVD. Mean and median DHA intakes among women of childbearing age (n 128, 18–34 years) were estimated to be 169 mg/d (sem 17) and 126 mg/d, respectively. Of these women, 27·7 % had a daily intake >200 mg DHA and 15·9 % had an intake >300 mg DHA. We noted that 13 % of Quebecers take ≥1 capsule of fish oil/d.ConclusionsConsumption of marine food products and EPA + DHA among Quebecers clearly appears to be lower than international recommendations. Since EPA + DHA confer health benefits and may reduce health costs, strategies to increase their consumption should be implemented to improve public health in Quebec.