bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Fauna of Sand and Mud Banks Near the Mouth of the Exe Estuary
Authors: Holme N. A. 
Published: May 2009

Erosion of Dawlish Warren, at the mouth of the Exe Estuary has resulted in a redistribution of sand, which has come to lie in close proximity to certain of the original mud banks.Quantitative collections of the macrofauna were made along a traverse passing from the newly deposited sand to the old mud bank, stations all being at about half-tide level.Measurements of salinity, temperature, pH, currents and wave action show that these are similar for all stations. Thus it has been possible to observe the distribution of the fauna in relation to the type of soil without the usual complications due to differences in other factors.
Responses ofBranchiomma Vesiculosum(Montagu) to photic stimulation
Authors: Nicol J. A. C. 
Published: May 2009

InBranchiomma vesiculosumdecrease in light intensity causes the animal to contract and withdraw into its tube. A decrease, never an increase, in illumination is the effective stimulus. When repeatedly stimulated the animals quickly become adapted to intensity changes and no longer respond.The minimal effective intensity change has been determined for a range of intensities. ΔI/I is found to increase in low light intensities, and to be fairly constant in intensities over 50 lux. The animals are least sensitive to red light; sensitivity increases in shorter wave-lengths.
The Relationship between State of Maturity and Chemical Composition of the Whiting, Gadus merlangus L
Authors: Bull H. O. 
Published: May 2009

In the whiting, no significant changes occur in the composition of the muscle substance, either throughout the year, or with increasing age, or during ripening of the gonads.The amount of fat in the liver is very low in immature fishes, increasing greatly with age, and reaching its maximum just after the commencement of the ripening of the gonads. It then falls off, reaching its lowest value amongst mature fishes in the “Spent” stages. Males are richer in liver fat than females.Immature fish have a decidedly higher protein content in the liver than have mature fish.
The Preservation of Fishing Nets by Treatment with Copper Soaps and Other Substances
Authors: Atkins W. R. G. 
Published: May 2009

1. Under the conditions of the tests cotton and hemp nets became rotten in Aquarium tank water in two months or less in summer, in 4½–5½ months in winter.2. A mixed copper soap, containing oleate, stearate, and palmitate, is as good, probably rather better, than is copper oleate as a net preservative.3. “Cuprinol,” a petroleum acid copper soap, is better than the fatty acid soaps, both in fresh and in salt water. It is more than three times as expensive, however.
Herring Investigations at Plymouth. I. Methods of Collection and Treatment of Data
Authors: Ford E. 
Published: May 2009

Towards the end of the year 1924, the present writer commenced a statistical study of random samples from commercial landings of herrings at Plymouth, in order to obtain information on the two following questions:—(a) Upon what year-class or year-classes of herring was the season's fishery of 1924–25 concentrated?(b) Did the fishes landed throughout that season appear to conform to a single morphological type?
On the Biology of Calanus finmarchicus, I. Reproduction and Seasonal Distribution in the Clyde Sea-Area during 1932
Authors: Nicholls A. G. 
Published: May 2009

1. Fortnightly samples were taken with a fine-meshed net in single vertical hauls at different positions in the Clyde Sea-Area.2. Each stage of Calanus present, from ovum to adult, was counted, and charts were constructed expressing these results for one year as total numbers and as percentage composition.3. Calanus passes the autumn and early winter mainly in its Stage V copepodite form.4. In general, total numbers were high in September, 1931, and fell steadily to a minimum in March; in Loch Fyne the minimum occurred i n April.5. A sudden increase was observed in May and numbers rose to maximal values; the decline also was sudden.6. Reproduction began in February and three plainly marked breeding periods were observed between February and July.7. The time taken by the egg in developing into the adult was four weeks.8. The total life of a Calanus during the summer was estimated to be about two and a half months; in winter it is five to six months.9. In Loch Fyne a noticeable lag occurred during the winter and early spring.10. The number of Calanus present in the autumn of 1932 was considerably less than.at the same time in 1931. This may have been due to a shortage of food.
On the Biology of Calanus finmarchicus. III. Vertical Distribution and Diurnal Migration in the Clyde Sea-Area
Authors: Nicholls A. G. 
Published: May 2009

1. Previous work on vertical distribution and diurnal migration is described.2. The diurnal migration of Calanus was studied on two occasions in Loch Fyne (January and July, 1932).3. Vertical hauls were taken every three hours with a closing net dividing the total depth into six sections.4. The results for each copepodite stage of Calanus are discussed, and January and July conditions are compared where possible.5. Ova and nauplii were observed to be most abundant in the top 30 metres.6. Copepodite Stages I, II, and III were most abundant above 30 metres and only the third copepodites showed any tendency to descend as the light increased.7. Stage IV showed a migration towards the surface at night, but were generally distributed during the next day.8. It is suggested that the results for this stage are probably confused owing to its transitional nature between the young stages living at the surface and Stage V Calanus living in deep water.9. Stage V was found always in deep water, slight diurnal changes being ascribed to the presence of such Calanus as were about to moult into adults.10. Females showed definite diurnal migration in both January and July.11. Males showed a general distribution and migrated in small numbers towards the surface at night and away from it during daylight.12. Stage V copepodites and females both lived nearer the surface in January than in July, correlated with seasonal changes in the intensity of the sunlight.13. The presence of swarms of Calanus at the surface under conditions of bright sunlight is discussed.
On the Marina Cladocera from the Northumbrian Plankton
Authors: Jorgensen Olag M. 
Published: May 2009

From an analysis of previous records of E. nordmanni, considered in conjunction with those furnished by the present investigation, the following points of interest emerge.1. E. nordmanni, while being generally distributed in the North Sea and adjacent waters throughout the summer months, has been shown to breed freely in inshore waters in early summer and again in autumn when maximum numbers of individuals are obtained.2. These two periods of maximal abundance are produced as the result of successive parthenogenetic broods and alternate with periods of depression. This is indicated not only by the sexually-produced winter-egg, but also by a reduction in the number of embryos contained in the brood chamber and consequent change in body-shape. This serves to show that the supposedly distinct races, described as being characteristic of the North Sea and the Baltic, have no doubt been founded on material taken at different periods of the agamic phase.
The Larval Development of Ophelia Bicornis Savigny
Authors: Wilson Douglas P. 
Published: May 2009

Fertilizations of Ophelia bicornis Savigny were made and the larvae reared. This is the first time the larval development of any member of the family Opheliidae has been described.The trochosphere is small and somewhat yolky; it has a broad prototroch, a narrow telotroch, a strong apical tuft and a long anal cilium.Annulation is accompanied by the appearance of parapodial lobes and bristles. When the first pair of bristles of the third setiger protrude the larva is ready to metamorphose. It has two, sometimes three eyes.The larva in its later stages can adhere strongly to solid objects, such as sand grains, by a secretion from the four anal papillae and the parapodial lobes. This is interpreted as an adaptive aid to settlement on sand banks swept by strong currents.At metamorphosis the larval external cilia are lost and the bristles rapidly elongate, especially those of the third setiger.Some of the larval bristles are slightly winged. So far only capillary bristles have been known in the Opheliidae.It is pointed out that a development such as that of Ophelia is more typical of polychaetes as a whole than are the developments of certain species commonly used as text-book types.
The Structure and Life History of Some Minute Prosobranchs of Rock Pools:Skeneopsis Planorbis(Fabricius),Omalogyra Atomus(Philippi),Rissoella Diaphana(Alder) andRissoella Opalina(Jeffreys)
Authors: Fretter Vera 
Published: May 2009

The external features ofSkeneopsis planorbis(Fabricius) are described and compared with those ofOmalogyra atomus(Philippi),Rissoella diaphana(Alder) andR. opalina(Jeffreys).The foot has a large posterior mucous gland (Figs. 1 and 4,Pm; PI. IV, figs. 1 and 2,Al,Pl), its secretion forming a thread on which the mollusc can climb from one level to another.Correlated with their small size are modifications of the pallial organs.Skeneopsis, the largest and least specialized, has a bipectinate osphradium, but the gill is reduced to nine filaments; the anus lies well within the mantle cavity. In the other genera osphradium and ctenidium are lost, though the latter may be represented inRissoellaby a small tract of ciliated epithelium. In the absence of a ctenidium the animals depend entirely upon pallial respiration and the stream of water through the mantle cavity is maintained by other means: from the anus strips of ciliated epithelium pass forward to the mouth of the mantle cavity, causing a strong exhalant stream and carrying away the faecal pellets. There is a compensating inhalant flow. The kidney (PI. IV, figs. 1 and 2, K), with its rich vascular supply, has migrated into the tissues of the mantle, increasing its respiratory efficiency.
Studies on British Laminariaceae. I. Growth in Laminaria Saccharina (L.) Lamour
Authors: Parke Mary 
Published: May 2009

The production, longevity, growth, regeneration and reproduction of Laminaria saccharina (L.) Lamour. on the Devon and Argyll coasts are described.Bathymetric zone and habitat control the fertility and longevity of the gametophyte and consequently the production of the sporophyte. Sporophytes develop at the higher levels during the winter, early spring, late summer and autumn, and at the lower levels during spring, summer and autumn.Longevity of the sporophyte depends on season of germination, bathymetric zone and habitat. Winter sporophytes rarely persist to maturity. Spring sporophytes form the bulk of all L. saccharina populations except on very sheltered coasts in the sublittoral zone where summer sporophytes may be equally numerous. On the British coast the life-span of a L. saccharina sporophyte does not exceed 3 years.
The anatomy of the body wall and appendages inArenicola marinaL.,Arenicola claparediiLevinsen andArenicola EcaudataJohnston
Authors: Wells G. P. 
Published: May 2009

Worms for dissection, or for museum preservation, should be prepared by the magnesium-formalin method, of which two modifications are given in the text.The body ofArenicolais differentiated into: (a) an achaetous ‘head’, comprising the prostomium and a small number (probably two) of subsequent segments, (b) a ‘trunk’, composed of a number, varying somewhat with the species, of chaetigerous segments, and (c) a ‘tail’, which may or may not be chaetigerous according to the species. The method of subdividing the body according to the distribution of the gills, so often met with in the literature, is misleading because it conceals the very fundamental differentiation between ‘head’ and ‘trunk’.The main layers of the body wall are described. There are grounds for supposing that the circular muscle layer plays a greater part than the longitudinal in the maintenance of a postural fluid pressure in active worms.
The seasonal variation in weight and chemical composition of the common British Laminariaceae
Authors: Black W. A. P. 
Published: May 2009

The seasonal variations in the total ash, crude proteins, mannitol, laminarin and alginic acid contents are given for monthly samples of the Laminariaceae,L. cloustoni, L. digitataandL. saccharinafrom November 1946 to October 1948, samples ofL. digitataandL. saccharinahaving been taken at different localities to determine the effect, if any, of the degree of exposure on the chemical composition.The results agree favourably with those of the first 2 years examined and indicate that, with only a few exceptions, results might be reproducible in the corresponding season of any year, and it should be possible, therefore, to predict the approximate composition in subsequent years.As before, the marked seasonal variations in chemical constitution occur in the fronds, where the bulk, if not all, of the photosynthesis occurs. The stipes undergo some variation parallel to that in the fronds, but within narrower limits, while laminarin is absent throughout the year.
A note on the barnacle larvae of the Clyde Sea Area as sampled by the Hardy Continuous Plankton Recorder
Authors: Barnes H. 
Published: May 2009

A series of results is presented on the barnacle larvae population of an area of the Firth of Clyde, over a 15-day period in the spring taken by means of a modified Hardy Plankton Recorder.The records and observations on barnacle settlement indicate that the larval population was considerably greater than usual.The total larval population showed no great fluctuations from day to day, and on a given day the composition of the population over a wide area was often reasonably constant.Evidence is presented that there is no great depletion of the population between Nauplius III and cyprid stages. It is suggested that the depletion previously reported may be due in part to the method of sampling or to the conditions at the time of sampling.During the time when the evidence indicates no depletion of population there was a heavy diatom outburst, which in this instance did not appear to interfere with the larval development.Data are given on the density of settlement.
On the production of living matter in the sea off Plymouth
Authors: Harvey H. W. 
Published: May 2009

A study, now in progress, of the phosphorus cycle in the sea off Plymouth required some knowledge of the amount of plants and of several ecological groups of animals. There were no existing data except for zooplankton and the larger net-caught phytoplankton.From information supplied by friends and colleagues, it was possible to make tentative estimates of the average biomass of other groups of animals occurring below unit area of the sea.
The bottom fauna of Great West Bay
Authors: Holme N. A. 
Published: May 2009

An account is given of the bottom-fauna of Great West Bay from samples taken in 1948 with a new sampler. Comparison is made with a similar survey made by Mr E. Ford with the Petersen grab in 1923.The deposits contain a fair proportion of mud, and the ‘EcVg’ communities denned by Ford dominate the area. Within the Bay are found fairly dense beds of Turritella communis, Lutraria sp., Callianassa subterranea and Spisula solida.No marked changes in the fauna seem to have occurred since the earner survey. The fauna is briefly compared with that of the Plymouth area.
Bionomics of the poor-cod (Gadus minutusL.) in the Plymouth area
Authors: Menon M. Devidas 
Published: May 2009

The volumetric and qualitative analysis of the food ofGadus minutushas been discussed. The post-larvae feed entirely on copepods, mostlyPseudocalanus elongatus. The O-group feeds on copepods, small decapods, amphipods, polychaetes and isopods. The adolescent and adult groups feed on larger decapods likeProcessa canaliculata, Galatheaspp. andPortunusspp., fish, polychaetes and amphipods.The age and rate of growth ofG. minutushave been computed from a study of the supra-occipital crest. These age determinations have been correlated with the age determined by scales, otoliths and size-analysis. Back-calculations have been made by graphical method and by using the Lea-Dahl formula. The differences between the back-calculated lengths and actual observed lengths are negligible.
Changes in the bottom fauna of Weymouth Bay and Poole Bay following the severe winter of 1962–63
Authors: Holme N. A. 
Published: May 2009

Anchor-dredge samples of the benthos in Weymouth Bay and Poole Bay were taken after the severe 1962–63 winter to ascertain what changes in the fauna had occurred. The same station positions as had been previously sampled in 1958 and 1959 were re-sampled in 1963–64 and the results from each Bay compared.Most species had survived the previous winter, when sea temperatures had probably been at 3° or below for about a month, but populations of the bivalve molluscs Venus verrucosa and Venerupis rhomboides, previously common in the area, had suffered severe mortalities, none being taken in the 1963–64 samples. The brittle star Acrocnida brachiata had also disappeared from the samples, and many other invertebrates appeared to have declined in numbers. Two cold-water species, Spisula elliptica and Buccinum undatum, showed if anything a slight increase, perhaps reflecting colder sea temperatures over the past few years. Crepidula fornicata also showed an increase in numbers.Mortalities were not necessarily of species close to the limits of their range, some of the latter having survived with no noticeable decline in numbers.
Fine structure of the secretory epithelium in the hypobranchial gland of the prosobranch gastropod mollusc Buccinum undatum L
Authors: Hunt S. 
Published: May 2009

The secretory epithelium in the hypobranchial gland of Buccinum undatum L. consists of a single layer of elongated cells resting upon a basement membrane which overlies layers of connective tissue and muscle. Three principal types of cell are present. Two of these participate in the actual production of the mucinous secretion while the third is a ciliated cell. The ciliated cells also bear numerous microvilli and contain abundant microtubules and microfilaments. Neuronal contacts with the ciliated cells can be detected.The secretion product of the gland is a loose association of acid mucopolysaccharide and glycoprotein and the cells secreting these two materials can be clearly identified. Those secreting acid mucopolysaccharide have been called acid mucin cells while those secreting glycoprotein have been called goblet cells because of their resemblance to intestinal goblet cells. The acid mucin cells are large and distended with an amorphous mass of electron luscent material. This material is strongly metachromatic in the light microscope when stained with toluidine blue. Newly secreted acid mucopolysaccharide is contained within membrane-bound vacuoles where it exhibits a whorl-like or lammelar form. This latter fine structure is lost as the vacuoles coalesce filling the cell. The goblet cells are smaller and contain discrete globular, membrane-bound, packets of electron dense material. These do not stain metachromatically. Both types of cell release their contents by rupture of the cell membrane at the epithelial surface.
On the genus Golfingia (Sipuncula) in the Plymouth area with a description of a new species
Authors: Gibbs P. E. 
Published: May 2009

A new species of the genus Golfingia (phylum Sipuncula), belonging to the subgenus Phascoloides Fisher, is described from the Plymouth area.Studies of the local populations of G. (Golfingia) elongata have shown the species to vary considerably in some important taxonomic characters, in particular, the number of retractor muscles: over 13% have only two or three retractors instead of four.Notes on, and a key to, the species of Golfingia found around the British Isles are given.
The histology and histochemistry of the pedal glandular system of two limpets,Patella vulgataandAcmaea tessulata(Gastropoda: Prosobranchia)
Authors: Grenon J.-F. , Walker G. 
Published: May 2009

Patella vulgatapossesses nine different pedal glands, six of which pour their secretions on to the sole. Proteins secreted by the marginal gland into the marginal groove are used for locomotion, especially when the limpet moves off following a period of adhesion. Another protein-secreting subepithelial gland, sparsely present throughout the foot, is also believed to be used in locomotion. A third gland type is present in the epithelium of the sole. The secretion of these epithelial mucocytes which is a weakly acidic muco-polysaccharide (MPS) is likely to have a locomotory function. Three other sole glands secrete highly viscous acidic MPS. Their secretions are likely to have an adhesive function. The three other glands present in the foot are contained within the side-wall. Of these, two are believed to secrete mucus to protect the animal against desiccation during emersion; and the other, present only in youngP. vulgata, pours its acidic MPS secretion into the epipodial streak. This secretion consolidates debris before it is cleared from the pallial cavity; in adult animals, muscular contractions of the foot are powerful enough to clear debris without the help of the epipodial gland.InAcmaea tessulatathe six glands present open out on to the sole and correspond in position, composition and function to the six glands of the sole ofP. vulgata. There are no glands within the side-wall.
The feeding behaviour of the featherstar Antedon bifida (Echinodermata: Crinoidea)
Authors: La Touche Robert W. 
Published: May 2009

The ecology and feeding behaviour of Antedon bifida bifida (Pennant) were studied in situ at five sites on the east and west coasts of Ireland. These encompassed a range of different habitats and hydrographic conditions, including currents of varying intensity, oscillations due to wave action, and multidirectional water movements.Unlike other comatulids hitherto studied, this species was found to be relatively unspecialized in its choice of habitat and to display great flexibility of movement in its arms and pinnules which enable it to adapt to and feed in each of the different types of water movements described. Neither diurnal nor tidal feeding rhythms were observed, the animals being found to feed almost continuously. The relatively unspecialized nature of this species is discussed in relation to the almost cosmopolitan distribution of the genus Antedon.
Investigation of a nutrient-growth model using a continuous culture of natural phytoplankton
Authors: Jones K. J. , Tett P. , Wallis A. C. , Wood B. J. B. 
Published: May 2009

Phytoplankton from Loch Creran, Argyll was maintained in continuous culture for 41 days. During most of this time the mixture of species retained the diversity and dominance pattern typical of summer phytoplankton in the loch, notwithstanding the manipulation of algal nutrient status to bring about phosphorus control of growth. Results suggest that most detritus was washed out early in the experiment.The aim of the experiment was to test the applicability to natural multispecies phytoplankton of part of Droop's (1974, 1975) model of nutrient-limited algal growth. ‘Quasi-steady states’ with respect to concentration of chlorophyll, particulate carbon (PC), particulate phosphorus (PP) and particulate nitrogen (PN), wereobserved at two levels of input of dissolved inorganic phosphorus. At other times the algal phosphorus quota (estimated from the ratio of PP to PC) varied from about 0·002 to 0·015 atoms P per atom C. Specific growth rate was estimated from the rate of increase of PC. During part of the experiment, growth rate was linearly related to reciprocal phosphorus quota, thus confirming the applicability of the model.