Several specimens of an ichthyobdellid leech were found on Blennius pholis collected on the coast of Anglesey.

The leech resembles Abranchus sexoculatus (Malm), a rare form only recorded previously from Sweden and not yet adequately described. Slight differences, however, indicate that it may be a distinct species and the name Abranchus blennii is provisionally put forward for it.

A short review of the genus Abranchus and a description of the appearance and structure of the leech follow.

My thanks are due to Prof. F. W. Rogers Brambell for his encouragement and advice; and to Mr W. H. Leigh-Sharpe for advice regarding the literature.

Notable catches of boar fish (Capros aper) were taken near the Eddystone on 30 October and in early November 1951. From what is known of the distribution of boar fish and from the hypothesis on the genesis of “submarine eagres” in canyons on the continental slope, a further hypothesis has been derived to explain this occurrence. It is suggested that strong west to south-westerly winds on 24 September created conditions to produce a submarine eagre the following day, and that this swept a shoal of boar fish from the yellow-coral encrusted walls of a submarine canyon in the southern edge of the Celtic Sea on to the continental shelf. Thence during quiet weather the shoal was carried by currents to the neighbourhood of the Eddystone at about 6 miles a day. Further deductions which lead to means of checking the present hypotheses have been drawn.

[The following Tables record the measurement and enumeration of a number of characters in certain samples of Herrings taken in the neighbourhood of Plymouth. The work was carried out as part of a general scheme for studying the question of the existence of local races of herrings around the British Coasts, which was organised by the Board of Agriculture and Fisheries. In consequence of the war there is no immediate prospect of the figures being analysed and compared with similar figures relating to fish obtained in other localities. It has therefore been thought advisable to place them on record as they stand, so that they may be available for other workers at any time. The short explanatory statement of the methods employed was prepared by Dr. Orton, who had charge of most of the work, to accompany the figures when they were sent to the Board of Agriculture and Fisheries, and was not written by him with a view to publication. The drawings have been made by Mrs. Sexton.—E. J. Allen.]

Coelomic fluid from the edible sea urchin Echinus esculentus (L.) has in vitro bactericidal activity against the marine pseudomonad, designated strain No. 111 (Wardlaw & Unkles, 1978). This particular bacterial strain was chosen because of its highly characteristic jet-black, agar-digesting colonies on marine agar plates which permitted it to be easily distinguishable from contaminants in bactericidal tests. Bactericidal activity is localised in the cellular components of the coelomic fluid, particularly in the red spherule cells (Messer & Wardlaw, 1980) and is demonstrable in almost all animals tested.

The classification of the Rissoidae has been, and continues to be, based largely upon shell characters. In a group of small animals of variable form this has resulted in a state of considerable taxonomic confusion. Ponder (1965, 1967, 1968), in his works on the New Zealand Rissoidae, attempted to clarify, what he termed, the existing ‘pigeon-hole classification’ in the light of more detailed anatomical investigation. He observed (Ponder, 1967) that ‘many wrong assumptions can be drawn from the study of the shell alone’. In an earlier work Johansson (1939) had also tried to relate the taxonomy of the Rissoidae to anatomical features.

‘Giant’ nerve cells have always attracted considerable interest because of the technical possibilities they offer to experimental biologists, for as well as being easy to impale with microelectrodes they can be dissected away from non-nervous tissues and used for bio-chemical analyses.

The influence of the lunar phases and tidal range on the fish capture was analysed in a tidal flat in Barra do Paraguaçu (Baía de Todos os Santos). The sampling was realized in the flood tide and ebb tide of the spring (full moon) and neap (waning moon) tides, between June 2007 and May 2008. At all sampling occasions, two parallel drags were accomplished to the tidal flat, in the same direction of the current, in a 100 m long area marked on the beach beforehand, using a seine net of 15 m × 2.0 m with a mesh of 12 mm between adjacent knots. A total of 2312 fish specimens were captured (26.5 kg), belonging to 75 species from 45 families. The mean number of captured fish was significantly larger in full moon at ebb tides, while the mean weight in the captures was larger in ebb tides. There was significant difference in number of species, number of fish, richness and diversity between full and waning moons. The number of fish and biomass were significantly different between tides. Significant differences were found in community structure regarding trophic groups in relation to tide and moon, although the classic diversity indices did not capture this effect between tides. Furthermore, it was possible to identify preferences of occurrence related to the change of tide in dominant species.

The bigfin reef squid Sepioteuthis lessoniana is a neritic species widely distributed in coastal waters of the Indo-Pacific region and is of interest to fisheries for its high commercial value. Squid samples were collected from Keelung (KL) and Penghu (PH), around northern Taiwan from October 2012 to September 2013. A total of 949 squid were examined, and 620 squid were aged using statoliths. The age range of the squid in KL (55–183 days) was similar to that in PH (77–186 days). The squid hatched almost year-round, except in January and December in KL. Two seasonal cohorts were identified: a spring cohort (hatched in March to May) and an autumn cohort (July to October). Concentrations of nine trace elements in statoliths were analysed using solution-based inductively coupled plasma mass spectrometry (ICP-MS). Significant differences in Fe/Ca, Cu/Ca and Sr/Ca were found between the two locations, while significant differences in concentration ratios of Sr/Ca and Ba/Ca were noted between the two seasonal cohorts. Results of a principal component analysis and cluster analysis varied in life-history traits between the two geographic stocks and in elemental concentrations between the two seasonal cohorts. Squid in KL and PH might undertake different migration routes, while seasonal variability in oceanographic conditions was apparent in the two locations.

It is generally believed that lecithotrophic larvae of annelids do not possess functional excretory organs. However, as in certain annelids the planktotrophic trochophora larva has been secondarily modified into a lecithotrophic developmental stage and because protonephridia are characteristic for the trochophora, lecithotrophic developmental stages should also possess such organs. To test this assumption hatchlings of the orbiniidan Scoloplos armiger, which develops directly without a free-living larval stage, were investigated ultrastrucrurally. Each hatchling possesses a pair of protonephridia which lie caudal to the eyes and almost level with the frontal margin of the foregut. Each organ consists of three multiciliated cells, a terminal cell, a duct cell and a nephropore cell. The terminal cell bears a distally oriented hollow cytoplasmic cylinder, which surrounds the cilia. Adherens junctions connect this structure to the duct cell. Several clefts and pores perforate the wall of the hollow cylinder. Extracellular material covers the pores and clefts and thus may function as a molecular sieve during filtration. A comparison with the protonephridia of other annelid larvae reveals: (1) that one pair of protonephridial head kidneys consisting of a terminal cell, a duct cell and a nephropore cell must be assumed for the trochophore in the ground pattern of annelids and (2) that these organs are preserved when lecithotrophic larval stages evolved within the Annelida

A comparative study of Chorda filum populations from the British Isles (S 34‰) and the Baltic coast of Finland (S 6‰) has revealed differences in response by live adult thalli to treatment for 2 h with sea water of different salinities. Water uptake and loss by thalli differed significantly in salinities of х o‚ х 1/6, х ⅓ and х 1 ( = 34‰). British material showed severe cell disruption in freshwater whereas Finnish material did not. Killed thalli also behaved differently, British material showing little response to salinity treatment but Finnish plants continuing to react much as live tissues.

Anatomical differences between populations were also observed, cortical cells in Finnish plants being significantly smaller than their British counterparts. Diaphragms traversing lumens of British material were simple, entire structures, but those in Finnish plants were deeply dissected and complex in organization.

It is postulated that Baltic Chorda may have undergone a process of evolutionary divergence in response to its changed saline environment.

INTRODUCTION

Chorda filum (L.) Stackh. is one of several species of north Atlantic Phaeophyceae to be found in the inner Baltic Sea and Gulf of Bothnia; its geographical limit being associated with sea water salinity of approximately 4‰, (Waern, 1952; Hällfors et al. 1981). This species has been studied by Norton & South (1969) and South (1966) who traced the development of gametophytes and early sporophytes in culture media of different salinites. Although their cultures had been established from British material only, they felt able to argue from their results that the Baltic population did not constitute ‘… a different physiological strain specially adapted to the extreme environmental conditions prevailing there’.

continuous plankton recorder (cpr) samples from the english channel and adjacent celtic shelf, taken over the period 1958–1980, were analysed for sardine (sardina pilchardus) eggs. results showed the progression of sardine spawning along the english channel from west to east from march to august and a return from east to west from september to november. this corresponds with the two seasonal peaks of sardine egg abundance in the western channel: the main summer peak being in may/june, with a smaller autumn peak in october/november. long-term changes in sardine egg abundance in cpr samples showed a decline in summer spawning from the late 1960s, but no clear trend in autumn-spawned egg abundance. similar patterns were observed in the numbers of sardine eggs sampled by conventional plankton net tows at the time-series station l5 off plymouth. this supports the use of the longer time-series of sardine egg data at l5 as being representative of a wider area and emphasizes the importance in continuation of the l5 time-series.

A testate amoeba with organic test, isolated from sediments in the Firth of Clyde, Scotland, has been assigned to a new genus as Ovulina parva (Protista: Filosea) based on its unique light microscopic and fine structural morphology. The hyaline to amber test is ovate (~15×ll µm) with a terminal aperture that is either unadorned or with a shallow collar. Hyaline, long-tapering, pointed, sometimes branched, pseudopodia emerge directly from the aperture or from the periphery of a thin web of hyaline cytoplasm. The nucleus (~5 μm) with a central nucleolus (~2 μm) is located at the posterior of the cytoplasm. The fine structure of the test, examined by scanning and transmission electron microscopy, shows it is entirely organic with an irregular to granular surface. Scattered elongate pits (~1 μm long) without perforations are distributed irregularly on the surface. Ectoplasm is distributed within a fine fibrillar envelope lining the test. The endoplasm is ovoid and contains anteriorly located vacuoles enclosing densely-staining bodies with chromatin-like filaments which appear to be bacterial prey in late stages of digestion. This is further corroborated by light microscopic observations that bacteria are cleared from the surface of the culture dish within the circumference of the pseudopodia. The mitochondria (0.5–1.0 μm) have tubular cristae and some are located in the vicinity of peroxisomes (~0.5 μm) surrounded by a single membrane and with a finely granular matrix. Minimum doubling time in our cultures was 28.4 h, and the testate amoeba exhibits remarkable salinity tolerance growing in media ranging from 0 to 35% salinity.

Between August 2005 and July 2007, 376 Guiana dolphin (Sotalia guianensis) encounters were documented in Sepetiba Bay. For the purpose of this study all dolphin sightings were classified as groups or aggregations. Groups (N = 268, x = 20, range = 1–90) consisted of dolphins in apparent association usually engaged in the same behaviour and moving in the same direction. Aggregations (N = 108, x = 204, range = 100–450) consisted of temporal association of numerous groups gathered in an area, totalling several hundred individuals usually engaged in the same behaviour but not necessarily moving in the same direction. Guiana dolphin groups and aggregations differed significantly in behavioural activity, spatial and temporal distribution and age composition. Most aggregated dolphins were engaged in foraging/feeding activities and primarily located at the interior of the bay, and also, aggregations were more likely recorded during morning hours and had more neonates and calves present when compared to groups. The plotted GPS records of aggregations formed two distinct clusters of distribution within the bay, indicating potential areas where conservation strategies could be implemented.

Pico-size cells with a red fluorescence signature similar to marine free-living prochlorophytes have been detected by flow cytometry throughout the fresh and brackish waters of the Changjiang Estuary in August 2005. These cells could be discriminated from Synechococcus by their lack of orange (phycoerythrin) fluorescence, from Prochlorococcus by their larger side light scatter, and from picoeukaryotes by their smaller side light scatter and much lower red (chlorophyll) fluorescence. The maximum abundances of these Prochlorococcus-like particles reached 3×104 cells ml-1 in the low salinity zone upriver and declined rapidly seaward. While Synechococcus was scarce and Prochlorococcus vanished in the brackish regions, the Prochlorococcus-like cells overnumbered the picoeukaryotes and became the predominant pico-size auto- fluorescing particles there, implying they might play an important role in this estuarine ecosystem and worthy of further investigation.

This study examined the reproductive ecology of eight Eastern Pacific deep-sea octocorals, collected from Washington to Southern California. The sexuality, reproductive mode, oocyte size, and fecundity of each species were identified using histological techniques. This research increases the knowledge of basic life histories of deep-sea corals. Swiftia simplex had the highest total fecundity of 42.53 (±9.82 SE) oocytes per polyp. Mean oocyte diameters in S. simplex and S. pacifica females differs among sample months. Swiftia pacifica and S. kofoidi had the lowest total fecundity: 4.6 (±2.06 SE) and 3 (±1.53 SE) oocytes per polyp, respectively.

At Looe, Cornwall (south-west England), engineering problems have resulted in the Sewage Treatment Works operating on saline rather than the typical freshwater sewage input. Saline water enters the system at all stages of the tide, except low water, mainly through the open-jointed sewers embedded in the mud of the Looe River Estuary, and causes a cyclical salinity regime within the works (Jones & Johnson, in press). A consequence of this seawater intrusion is the replacement of the freshwater macroinvertebrate community commonly associated with biological filters by two species of euryhaline amphipods. In particular, Gammarus duebeni Liljeborg is permanently established at various sites in the works including the percolating filters and humus tanks (Jones & Wigham, 1988). The ability of G. duebeni to colonise and establish a breeding population at the works is probably a reflection of its wide tolerance to several environmental factors. This species is extremely euryhaline (Forsman, 1951; Sutcliffe, 1967; Pinkster, 1970) and can withstand marked hypoxic exposure (Bulnheim, 1979; Ritz, 1980). However, in addition to fluctuations in salinity and oxygen saturation, treatment works amphipods are exposed to relatively high levels of heavy metals associated with domestic and industrial inputs (Jones & Johnson, in press). Within the humus (secondary settlement) tanks, zinc concentrations are particularly elevated compared with the adjacent estuary, although there are considerable fluctuations in zinc levels experienced by animals due to the tidally based dilution of the incoming sewage (Jones & Johnson, in press).

The growth rate response of bacterial communities to the potential increase of dissolved organic matter (DOM) produced by the copepod Acartia tonsa was assessed in experiments conducted in three stations representing three contrasting aquatic environments (coastal embayment, shelf and ocean). Bacterial assemblages were inoculated in filtered seawater where A. tonsa had previously grazed. Utilization of DOM over time was evaluated after the addition of bacterial inoculums as the biomass changes in both ‘control’ and ‘copepod’ treatments. In the embayment and ocean a high bacterial growth was observed in the treatments with seawater where copepod were feeding. Additional field measurements of bacterial, primary production and zooplankton biomass support the idea that bacterial communities living in oceanic environments can be efficient to utilize the newly available substrate. Copepods play a key role not only as conveyors of carbon up through the classical food-web, but also generated significant amounts of bacterial substrate in the microbial loop food-web.

Reduction in survival under hypoxic conditions in the presence of sulphide has been repeatedly demonstrated in various benthic invertebrates. However, the reason for this reduction has not yet been clearly elucidated. In this study, the effects of sulphide accumulation on anoxic survival and anaerobic metabolism were investigated in the ark shell Anadara kagoshimensis. Ark shells from western Japan were experimentally exposed to 3 sulphide-accumulation levels under sustained anoxic conditions: accumulated H2S treatment (static incubation), decreased H2S treatment (semi-static incubation with daily replacement of incubation media), and inhibited H2S treatment (static incubation with the addition of antibiotics). Moreover, the effect of antibiotics on anoxic survival was examined under sulphide exposure. The decreased H2S and inhibited H2S treatments resulted in 1.5- and 3-fold increase in the anoxic survival time, respectively, when compared with the accumulated H2S treatment. Under anoxic sulphide exposure, the antibiotics addition did not affect survival time, suggesting the shorter survival time in the accumulated H2S incubation was probably due to sulphide toxicity. Glycogen consumption and propionate accumulation, which indicate activation of anaerobic metabolism, were observed in both accumulated and inhibited H2S treatments. However, glycogen consumption was significantly higher in the accumulated H2S treatment after a significant sulphide accumulation was detected in the incubation media. In addition, survival in the accumulated H2S treatment decreased rapidly, whereas no significant mortality was observed in the inhibited H2S throughout the experiment. These results likely suggest that the accelerated anoxic-driven mortality in sulphide-rich environments was partly due to the faster breakdown of glycogen.

The filter feeding bivalves Mulinia edulis and Mytilus chilensis, were exposed to a broad spectrum of concentrations and qualities of seston in order to compare the results of filtration rates measured volumetrically and gravimetrically, by both the traditional clearance method of Coughlan (1969) and the biodeposits method. Filtration rates, measured gravimetrically by both methods, tended to give similar results for both species, increasing with increase in seston and with decrease in seston organic content. With volumetric measurements, the filtration rates for both species also increased with the concentration of seston, however, in Mulinia edulis, the effect of the organic content of the food was less than that observed using gravimetric units, which is seen in the smaller slope of the regression equation (TFRv=−0·49). In the case of Mytilus chilensis there was no verifiable effect of the quality of the food on the filtration rate when expressed on a volume basis. The filtration rates of Mulinia and Mytilus measured by two methods and two units showed a similar behaviour with increase in the concentration of seston.

the tendency for marine fish to refuge in natural and artificial structures underwater is well documented, but the incidence of this behaviour among predatory sharks is not widely known. a sub-adult male nursehound scyliorhinus stellaris was tracked by intermittent acoustic telemetry over 168 days in a tidal sea lough. this individual, in-between undertaking nocturnal foraging excursions, refuged in at least five different narrow-entrance holes. refuge location was validated by underwater and surface observations during which time other nursehounds (sub-adult male and female), were also seen refuging, sometimes together. this indicates nursehound display philopatric behaviour centred on aggregation in ‘home’ refuges that, in this case, were labyrinthine rock systems.