This paper describes the species composition, vertical distribution, and the seasonal changes in the biomass of subtidal macrophytes in Sobol Bay (Peter the Great Bay, Sea of Japan). The samples were collected in the depth-range from 0.5 to 4 m. A total of 65 macrophyte species were identified, among which were 10 species of Chlorophyta, 17 of Phaeophyceae, 37 of Rhodophyta and 1 of Magnoliophyta. Multivariate analyses were performed to detect spatial and temporal variations. Maximum species richness was registered in June, with a particularly dramatic biomass increase of brown algae. Both the number of species and the biomass of macrophytes decreased with increasing depth. Depth clearly affected the patterns of seasonal fluctuations of the species composition and biomass. In the study area, the species composition of the shallow-water algal assemblages was more stable throughout the year compared to that of the algal assemblages found in deeper waters. In total, four macrophyte assemblages were identified in the bay. A Phyllospadix iwatensis and Coccophora langsdorfii dominated assemblage occupied muddy-gravel bottoms in depths from 0.5 to 2 m throughout the year. An assemblage, co-dominated by annual brown algae Desmarestia viridis and Costaria costata, occurred at depths more than 3 m at late spring. Two other assemblages occurred on the rock and boulder bottom at 0.5–2 m depths, but they were temporally separated. An assemblage co-dominated by annual laminarian algae (Undaria pinnatifida and Costaria costata) developed at late spring and was succeeded in the autumn and winter by a Tichocarpus crinitus, Ulva lactuca, Sargassum pallidum and Codium fragile co-dominated assemblage. A comparison between the data obtained in the present study and the results of a previous study conducted in 1927 shows that the macrophytes assemblages in Sobol Bay underwent little change.

The genus Trachytedania Ridley, 1881 (Porifera: Poecilosclerida), includes those tedaniidae sponges characterized by the presence of acanthostyles. To date, only five species of the genus Trachytedania have been described of which only three actually belong to this genus. Other species described as Tedania could be considered as Trachytedania because of the presence of acanthostyles in their skeletons. Some authors propose retaining Trachytedania as a subgenus of Tedania because of its skeletal structure. In this work, a taxonomic revision and consideration of the validity of the genus is provided. The morphology and anatomy of Trachytedania ferrolensis sp. nov. from the Ría de Ferrol (Spain, north-east Atlantic) are described in detail, and the types of the three valid species described as Trachytedania to date: Trachytedania spinata, Trachytedania patagonica and Trachytedania biraphidora are studied. A key to this genus is provided.

The abundance and community composition of phytoplankton are influenced by a suite of interacting environmental factors. Hong Kong's marine environment features a hydrographic gradient from an estuarine zone in the west to a transition zone in the middle and an oceanic zone in the east. Size fractionation combined with high performance liquid chromatography (HPLC) pigment analyses were used to investigate the phytoplankton communities in different hydrographic zones during summer (July–August 2009) and winter (December 2009–January 2010). Clear temporal and spatial variations in environmental parameters occurred among hydrographic zones. Results of principal component analysis (PCA) revealed that the major deviating factors among hydrographic zones were turbidity and salinity in summer and nitrate and phosphate in winter. Phytoplankton abundance showed significant temporal variations, but no zonal variations. Phytoplankton communities in all hydrographic zones were dominated by cells >5 µm in both summer and winter. Chlorophyll a concentrations for most size fractions correlated significantly with temperature. The high concentration of fucoxanthin indicated that the phytoplankton community was dominated by diatoms in both summer and winter, while dinoflagellates, cryptophytes, cyanobacteria and other minor groups occurred sporadically in low abundance. The spatial pattern of phytoplankton in Hong Kong's coastal seas did not reflect the hydrographic zonation, but the phytoplankton in the semi-enclosed Tolo Harbour and Deep Bay were different from those in the other zones.

Upwelling can determine important changes in community structure on rocky shores. However, studies on the meiofauna in areas of upwelling are scarce and do not include analysis on the species level for Copepoda Harpacticoida. The present study aimed to describe the Harpacticoida community in a region under the influence of coastal upwelling (Arraial do Cabo, Rio de Janeiro, Brazil). The hypothesis tested was that temporal differences in the fauna would be greater at the rocky shore more affected by upwelling. Samples were collected from the sublittoral of two rocky shores: Sonar, which is more exposed to upwelling, in January and June 2004; and Pedra Vermelha, which is a sheltered shore, in March and September 2002. Each sample consisted of four replicates collected by scraping epilithic algae along with the associated sediment. Weekly data on surface water temperature and nitrate content denoted stronger upwelling in 2002 compared to 2004. Nine genera of Copepoda Harpacticoida are reported for the first time for the Brazilian coast. Univariate indices identified no differences between rocky shores or seasons, whereas multivariate analysis indicated significant differences in assemblages between shores and between seasons. The strong variation in physicochemical conditions associated with upwelling favoured the dominance of opportunistic species, such as Parastenhelia spinosa. At the Sonar rocky shore, temporal differences were significantly stronger than at Pedra Vermelha, thereby confirming the initial hypothesis. These results indicated that the occurrence of upwelling had a very important role structuring the Harpacticoida assemblage at the species level.

In the Gulf of Gabès (Tunisia), a fleet of bottom longliners operates in summer and in the beginning of autumn targeting groupers. This fleet interacts with loggerhead turtles. During twenty trips in which 48,020 hooks were deployed, a total of 16 loggerheads were captured, most of them were juveniles, and direct mortality was estimated to be 43.75%. During the fishing operation, the hauling of the gear started one to three hours after and sometimes occurred immediately after setting. Results obtained show that the soak time did not affect the capture of turtles and target species, whereas it influenced the mortality rate of turtles. Bottom longline should be studied more in depth throughout the Mediterranean Sea, as well as parameters related to the interaction with sea turtles. However, mitigation measures to reduce turtle by-catch are urgently needed. In this way, we propose: (i) reducing the fishing soak time; (ii) experimenting with gear modification such as the use of circle hooks; and (iii) conducting an awareness campaign aimed at fishermen to show them how to deal with turtle by-catch.

Samples were collected from six pools in order to examine the distribution, body length, base colour and phenotypic diversity (chromatophore pattern) of Idotea granulosa populations on five different species of algae (Ceramium, Corallina, Chondrus, Fucus and Enteromorpha), on each of two shores. Holbeck (HOL) pools had significantly higher habitat heterogeneity in terms of algal species diversity than did those on the more exposed Filey Brigg (FB). Idotea densities were significantly higher and mean body size significantly smaller on Corallina than the other algal species. Isopods were significantly larger on Fucus. There was no significant difference in base colour frequencies between shores but there was a positive association between the brown base colour and Corallina and the green colour and Fucus.  The commonest chromatophore pattern morph was the granulosa-maculata that occurred in 44% of the isopods sampled and five out of ten chromatophore patterns accounted for <10% of the population. The uniformis morph was rare on both shores. There was no significant difference in chromatophore pattern frequency between the sexes. The lineata-maculata morph and maculata morphs showed a positive association with Corallina and Fucus respectively. There was a significant difference in chromatophore pattern frequency between adults and juveniles. The uniformis and maculata patterns occurred in higher frequencies than expected in the adult population whereas the reverse was true of the granulosa-maculata and lineata-maculata morphs.  A total of 85 different phenotypes were recorded from both shores, with 51 of these being exclusively found in HOL pools. Holbeck pools had a significantly higher isopod phenotypic diversity than did those from FB. There was no significant difference in phenotypic diversity between adult and juvenile Idotea at HOL, however juveniles had a significantly higher phenotypic diversity than did adults at FB. Overall, there was a significant positive correlation between rockpool algal diversity and isopod phenotypic diversity.

The genus Stoeba has 11 recognized species. Herein we describe a new species of Stoeba endemic from two oceanic archipelagoes off north-eastern Brazil (Fernando de Noronha and São Pedro e São Paulo), constituting the first record of this genus for the western Atlantic. Stoeba latex sp. nov. is characterized by its thickly encrusting to massive shape, stretched surface, brownish-red colour, and spiculation of calthrops and sanidasters with well developed spines; dichotriaenes and oxeas are absent. Stoeba and Dercitus are very closely related genera, and should probably be merged. The genus Stoeba now contains the following valid species: S. dissimilis, S. exostotica, S. extensa, S. lesinensis, S. natalensis, S. occulta, S. pauper, S. plicata, S. reptans, S. simplex, S. syrmatita and S. latex sp. nov. Several other species still await description. A key to the valid species of Stoeba is given.

Spring and autumn phytoplankton blooms are characteristic of those temperate marine waters where thermal stratification occurs during the summer months (e.g. Raymont, 1976). However, in well-mixed coastal waters the phytoplankton production cycle may consist of a single peak of growth during the summer (Boalch, Harbour & Butler, 1978; Wafar, Le Carre & Birrien, 1983). In a recent paper, Brander & Dickson (1984) considered evidence from the Irish Sea continuous plankton recorder which reflects the phytoplankton growth cycle largely in the well-mixed areas of the sea. These data suggested a single late peak of production, in contrast to the bimodal blooms which are known to develop in the stratified areas of the Irish Sea (Burrows & Sharpies, 1973; Slinn, 1974). The purpose of the present work was to establish the production cycle for Belfast Lough, which lies adjacent to the North Channel, an area of strong tidal mixing which forms the northerly exit for water from the Irish Sea (Lee & Ramster, 1981; Howarth, 1984). There have been no previous measurements of primary production in Belfast Lough. There was considerable interest in this topic in the early years of this century when the Royal Commission on Sewage Treatment (1908) heard evidence that nutrient inputs from sewers into the lough resulted in excessive growth of the green alga Ulva, which caused a nuisance as it decayed around the shores. Although there have been no recent reports of this phenomenon, several sewage works continue to discharge partially treated effluent to the lough. An aim of this work was therefore to assess the role of anthropogenic nutrient inputs upon phytoplankton growth.

The gastropod Littorina littorea shows increased mortality in the summer months when infected with digenean parasites. One possible cause of this mortality is impaired respiration in infected hosts. Respiration rates of L. littorea infected with three species of digenea of varying pathogenicity were measured: Cryptocotyle lingua, Himasthla elongata and Renicola roscovita. No evidence of altered respiration rates in infected snails was found.

The paragnaths are soft outgrowths of the crustacean exoskeleton lying close to the mandibles on the aboral side. They are sometimes termed the metastoma, for instance in Pike (1947) in Galathea squamifera Leach, or the hypopharynx by Wägele (1987) in the isopod Antarcturus Schultz. It should be noted however that Manton (1964) stated that the crustacean paragnath was not the same structure as the insect hypopharynx.

Three new species of Crambe are described from the upper and middle-southern coast of Chile, south-east Pacific. Crambe chilensis sp. nov. and C. amarilla sp. nov. are astroclone bearing species, while C. maldonadoi sp. nov. has sphaeroclones as asterose desmas. Morphological characters of Crambe were re-evaluated to consider this unsuspected high diversity of Crambe in the south-east Pacific. The main characters for the distinction of Chilean species as well as of other Crambe species were the live-colour; the shape and size of asterose desmas and (sub)(tylo)styles; the shape, number of categories and size-range of anchorate isochelae; and the presence/absence and dimensions of spined microxeas. An identification key for the Crambe of the world is provided. If astroclone and sphaeroclone desma-bearing species groups would represent two distinct evolutionary lineages, then the south-eastern/eastern Pacific Region would have been occupied by two evolutionary lineages with distinct life histories. The relatively high diversity of Crambe in the Chilean temperate coast, together with its occurrence in New Zealand's Oligocene, is suggestive of a likely wide distribution in Panthalassa, which contrasts to earlier suggestions of wide distribution in the Tethyan Realm only.

Biofilm-dwelling ciliates are a primary component of a biofilm, and play an important role in the functioning of microbial food webs by mediating carbon and energy flux into benthos from plankton. The carbon flux of biofilm-dwelling ciliates was studied at different trophic-functional levels within the colonization process in coastal waters of the Yellow Sea, northern China from May to June 2015. Samples were collected, using a glass slide method, at the time intervals of 1, 3, 7, 10, 14, 21 and 28 days from depths of 1 and 3 m. The carbon biomass of both total ciliates and all trophic-functional groups increased following the logistic growth curve model. During the whole colonization period, the bacterivores and non-selectives were generally the primary contributor to the carbon flux in young samples (<14 days), while the algivores and raptors predominated mature samples (14–28 days) at both depths. In terms of mature samples, however, the non-selectives and algivores were the primary contributors at a depth of 1 m, while the raptors accounted for primary contributions to the carbon flux at a depth of 3 m. Although the times to 50% maximum carbon biomasses were generally ranged 24 days at both depths, the maximum carbon biomasses were significantly higher at depth of 3 m than at 1 m. These results may provide useful information for ecological research on carbon flux from plankton to benthos in marine ecosystems.

Monthly samples retrieved from the previously unstudied Plym Estuary, from January 1994 to November 1994, were analysed for living and dead Foraminifera. An assemblage composed of three hyaline species; Haynesina germanica, Elphidium williamsoni and Ammonia beccarii var. batavus, was identified. Further samples were taken to assess depth distribution, microdistribution and lateral distribution, to compliment the original sample suite. A comparison of the dead assemblage to the live assemblage revealed similar species proportions in both assemblages, reduced test abundance in the dead assemblage, and the presence of rare estuarine and marine species in the dead assemblage. This study has revealed a complex interplay of species resulting in several foraminiferal blooms throughout the year; the largest occurring in May.

INTRODUCTION

A comparative survey on the capacity of several nitrogenous compounds to support marine phytoplankton growth showed urea as the best and D-glucosamine as the poorest supplier of organic-nitrogen at a concentration of 500 /g-at. N per litre (Antia et al., 1975a). The quality and degree of growth on glucosamine was always so inferior that the evidence appeared insufficient to establish whether this compound was actually being metabolized by the algae. By analogy with the substrate-utilization kinetics reported for growth of other micro-organisms such as yeast (e.g. Tseng & Wayman, 1975), the probability was considered that the glucosamine concentration used in the above survey may have been too low for adequate uptake under the test conditions chosen and that elevated concentrations, in facilitating such uptake, may provide unequivocal evidence of algal capacity for metabolism and utilization of this substrate. However, such concentration elevation would require to be below levels that may become inhibitory to growth, and these inhibitory levels may themselves vary from one species to another. Antia & Chorney (1968) reported 5 mM glucosamine to be toxic to growth of the cryptomonad Hemiselmis virescens, whereas McLachlan & Craigie (1966) observed growth of the diatoms Cyclotella cryptica and Thalassiosira fluviatilis on five times this level of concentration.

The accuracy of volume estimation in filling a marked tank by means of a plankton pump has been determined. The method even in its simplest form is satisfactory under good conditions. Further refinements, in which the plankton was filtered off, after filling a modified tank (for example with an overflow device) would no doubt increase the accuracy.

A device is described by which, using an ex-N.F.S. pump, a constant (but variable by selection) volume of water can be taken without the use of large tanks.

A small number of sets of samples taken with adequate volume control indicate the same order of variability as net hauls. Comparison of the distribution of x2 for paired samples with nets and pumps also indicates variation of a similar type.

These results suggest that the variability of net hauls is not entirely due to the variations in the volume of water filtered. Further work is in hand to elucidate this question.

1. In order that the Harvey method shall estimate without avoidable error the concentration of marine or freshwater phytoplankton, it is essential, firstly

Two new species of polyclads are described from the continental slope of the Gulf of Mexico. Specimens of Didangia carneyi sp. nov. and Oligocladus bathymodiensis sp. nov. were collected from the Louisiana slope at 610 m and 650 m, respectively. Didangia carneyi sp. nov. was collected from a natural wood fall, and is characterized by the presence of tentacular and cerebral eyes, an interpolated prostatic vesicle provided with two muscular accessory prostatic vesicles, and large glandular cells that surround the male atrium. Oligocladus bathymodiensis sp. nov. has a mouth anterior to the brain, a few cerebral and pseudotentacular eyes, four pairs of intestinal branches, and a ventral anal pore. Specimens of this species were collected on the margin of a hypersaline cold seep in association with mussels of Bathymodiolus childressi. All type material is deposited at the Field Museum of Natural History, Chicago, Illinois, USA.

The heart nerves of Praunus flexuosus Leach ( = Macromysis flexuosa White) have been stained with methylene blue applied in various ways. As a rule the animals were injected with a solution prepared immediately before use by mixing 1 part of 0–5 % solution of methylene blue in distilled water or of rongalit white with two parts of sea water. The injection was made into one of the posterior segments of the abdomen with the needle pointing forwards. When three or four animals are treated at the same time, usually in at least one of them the staining reaction takes a satisfactory course and its progress can be observed under the microscope, owing to the transparency of the tissues. In a few minutes after the injection some of the nerves are already visible. Later the coloration becomes more general and more intensive, but soon begins to fade out and can disappear completely.

This list contains 2 species of Tanaidacea, 6 of Isopoda and 28 of Amphipoda. These were all collected by myself in 1934–5, with the exception of 3 species of Amphipoda, which have not been entered in the Plymouth list although accounts of their capture at Plymouth have been published. These are Eusirus longipes Boeck, recorded by Hunt (1924); Gammarellus angulosus (Fabr.), by Kitching, Macan and Gilson (1934); and Gammarus zaddachi Sexton, by Serventy (1935).

The list is drawn up in the systematic order adopted in Plymouth Marine Fauna (1931), with a reference to a good illustration of each species. The dates and circumstances of capture are stated, and when a species has already been recorded from off the coasts of Devon and Cornwall by Norman and Scott (1906) a note to that effect has been made. The distribution is not stated, since recent accounts of the distribution of every species are available in the following works:

Tanaidacea and Isopoda: Nierstrasz and Stekhoven, 1930 (except for Synisoma acuminatana, q.v.).

Amphipoda: Chevreux and Fage (1925) or Stephensen (1929).

All the Amphipod species in this list are included in one or other of these publications, and almost all in both.

Every species has been referred to a specialist for identification. Tanaidacea and Eurydice truncata and Gnathia oxyurœa to J. H. Schuurmans Stekhoven of Utrecht; the other Isopoda to Prof. W. M. Tattersall of Cardiff; the Amphipoda to Dr. K. Stephensen of Copenhagen, excepting Gammarus zaddachi Sexton, which Mrs. Sexton herself has named.

Many field observations have been made on predation by a variety of fish species on the demersally spawned eggs of the Atlantic herring (Clupea harengus L.) (Dunn, 1898; Bowman, 1922; Hempel & Hempel, 1971; Toresen, 1985). Field observations on the predation of herring larvae by fish are comparatively rare although jellyfish medusae have been identified as larval predators (Van der Veer et al, 1983; Moller, 1984). Recently several experiments have been carried out on the predation of medusae and other planktonic organisms (Bailey & Batty, 1983) and of fish on herring larvae (Christensen, 1983; Fuiman & Gamble, 1987). Despite the lack of field observations Hunter (1984) considered that predation, most probably by fish, was the major cause of mortality in fish larvae.