Ferritin crystals and calcium granules are reported from the ventral ceaca of Steleuthera ecoprophycea (Amphipoda: Stegocephalidae) collected from the Snake Pit hydrothermal vent, Mid-Atlantic Ridge (3520 m).

In a series of earlier papers (Moore & Rainbow, 1984, 1989, 1992; Moore et al., 1994), the authors described the widespread occurrence of intracellular, octahedral crystals of ferritin in the ventral caeca of a range of stegocephalid amphipod species from the continental shelf epibenthos and oceanic plankton. The discovery at 3500 m of a new Steleuthera species (S. ecoprophycea), from a hydrothermal vent on the Mid-Atlantic Ridge was announced recently by Bellan-Santini & Thurston (1996), and a complete description is provided therein.

Oceanic ridge sites are notable for their tectonic activity and the presence of a diversity of trace metals at high concentrations is to be expected in hydrothermal plumes emanating from such regions (German & Angel, 1995). The detoxification of accumulated trace metals in the ventral ceaca of stegocephalid amphipods from uncontaminated environments is now relatively well known (see above), so it was of interest to investigate whether a vent stegocephalid showed an atypical presence of trace metals in detoxified form in cells of the ventral caeca. The results following from an opportunity to investigate this are reported herein.

Material was derived from a dive made by the submersible ‘Alvin’ at Snake Pit hydrothermal field, Mid-Atlantic Ridge (23°23′N 44°56′W), 3520 m, on 16 June 1993 (see Bellan-Santini & Thurston, 1996). Steleuthera ecoprophycea was preserved in 70% alcohol. Subsequently to dissection, the single pair of ventral caeca from each of the four damaged amphipods investigated were post-fixed in 4% glutaraldehyde. For electron microscopy and x-ray microanalysis in STEM mode, ventral caecal tissues were then dehydrated through 95% and absolute ethanol, cleared in propylene oxide, embedded in TAAB resin, sectioned at 0·5 μm (semi-thin sections) on a Reichert OmU2 ultramicrotome and examined without staining in a JEOL 100C electron microscope equipped with LINK system EDX energy dispersive x-ray microanalyser.

The final regeneration stages of the nitrogen cycle in the sea are believed to consist of the bacterial oxidation of ammonium-nitrogen to nitrite and finally nitrate-nitrogen. There have been many attempts to demonstrate the presence in the sea of marine counterparts to the terrestrial Nitrosomonas and Nttrobacter. (See Zobell, 1946, for bibliography of the earlier work.) Bacteria which can oxidize either ammonia or nitrite are easily demonstrated in samples of bottom material or water contaminated by land drainage or bottom deposits. On the other hand, there has been general failure to demonstrate the presence of such species in the upper layers of the open ocean.

It has been amply demonstrated that trawl fishing affects overall biomass, size and species structure of demersal fish communities, and an increasing number of studies are proving that this could have even greater unexpected effects on biological diversity. The aims of this study are: (1) to examine the temporal trends of several ecological diversity indices for middle-slope communities in specific locations within the Sardinian seas, which have been recently subject to increasing fishing capacity; and (2) to simulate the Shannon's entropy (H′) temporal trend, using a multiple linear regression, in order to investigate about the relationships between fishing effort and species diversity. The data come from 11 MEDITS trawl surveys (1994 to 2004). Temporal trends in fishing effort were analysed and ecological diversity indices were measured. Analysis was conducted for four areas (NW, NE, SE, SSW). Significant variations over time in both fishing pressure and ecological diversity indices were found for the southern zones. More precisely, the SE zone showed an increase in fishing effort (+120% in 2004), and a decrease of Shannon–Weiner's diversity. The SSW zone exhibited a 22.6% increase of fishing effort and a decrease of species richness. The best model of H′ incorporates species richness and fishing effort expressed as number of boats per trawling area. Our results seem to indicate that fishing pressure affected the species richness and the abundance of middle-slope species and that variation in ecological diversity indices differed with different levels of fishing effort.

Soleid eggs caught in the plankton off Algiers were reared and identified. Thus, the egg and the yolk sac stages of Microchirus ocellatus (L.) and M. azevia (Capello) were described, compared and differentiated from the corresponding stages of M. variegatus (Donovan). For the latter species, a large perivitelline space was often discernible.

In 1889, Cunningham referred some pelagic eggs caught near Eddystone (English Channel) to Solea variegata, owing to their similarity to the mature ovarian eggs of this species. Moreover, he considered the embryonic and larval stages described, illustrated and named ’species no. 1'by Raffaele (1888) as belonging to the same soleid. In further works, Cunningham studied the two-day-old larva (1890) and the newly hatched larva (1896). These papers and some others relating to Microchirus variegatus (Donovan, 1808) (present name of S. variegata) were reviewed by Ehrenbaum (1905), Padoa (1956), Nichols (1976) and Russell (1976).

Such eggs are often collected in the plankton of the Bay of Algiers, but I noted a great variability in their features. According to Quero et al.

Numbers of naked amoebae (Gymnamoebae) inhabiting the lower intertidal zone of two sandy beaches were estimated using a novel enrichment cultivation method. Samples were collected between June and September, 1999. Beach sand at Kames Bay, Isle of Cumbrae, Scotland contained on average 2604 amoebae cm−3 while at Dania Beach, Florida, USA, sand harboured 4236 amoebae cm−3. This is the first study to focus on the abundance of naked amoebae inhabiting a sandy beach. These numbers are higher than densities generally reported for shallow subtidal sands and show that amoebae must be considered in future studies on the dynamics of sandy beach communities.

In 1955, Kerkut recorded the spontaneous activities of a tube foot of Asterias rubens L. Such activity consisted of cyclical protraction and retraction phases, one complete cycle lasting on average some 6·5 min (S.D. 2·5). The duration of the protraction phase was on average 4·3 min. It is reasonable to assume that under the conditions of this experiment a similar level of hydrostatic pressure was attained as was found by Binyon (1964), namely 30 cm water. There then followed a fairly rapid retraction of the podium and a quiescent period of some 2·2 min duration. An individual podium would thus execute some 9·2 cycles/h.

A new species of Craniella from the Aleutian Islands is described. Craniella sputnika sp. nov. differ from all other species of Craniella in its habitus, absence of microscleres and size of spicules. The name refers to its resemblance to Earth's first artificial satellite, due to its spherical body with long spines. The new species was observed growing on another demosponge, Myxilla sp. We propose transferring two species currently in Craniella to Tetilla (Craniella ellipsoidea Hoshino, 1982 and Craniella laminaris (George & Wilson, 1919)) and two subspecies (Craniella globosa anamonaena Tanita, 1968 and Craniella laminaris symmetrica (Wilson, 1931)) from Craniella to Tetilla. As Craniella globosa anamonaena Tanita, 1968, is actually a species of Tetilla we suggest raising the subspecies to species rank as Tetilla anamonaena. Conversely we think that two species, Tetilla ovata (Thiele, 1898) and Tetilla hamatum Koltun, 1966 should be transferred to Craniella.

Study of living colonies of Salacia tetracythara Lamouroux, 1816, led to an accurate description of the hydranths and adjoining tissues. A mantle is reported for the first time for this species, lining stem, hydrocladia and hydrotheca. An adcauline nematocyst clump located in the median part of the column, composed of large microbasic mastigophores, is also reported as a new structure for sertulariids. The hypothetical modified tentacles noted by Billard (1925) are confirmed and re-described. Among the 22–28 tentacles of the hydranth in a circlet, two exhibit nematocyst-bearing organs connected at base. These organs are massive, racket-shaped, refringent, and composed of large microbasic mastigophores. They do not affect the tentacles in respect of their general shape and behaviour. One nematocyst-bearing organ can sometimes be linked to more than one tentacle depending on its size. The abcauline position of the two modified tentacles imparts a strong bilateral symmetry to the hydranth. This location explains why only one modified tentacle was previously described from preserved material, the second being hidden by the first when hydranths are retracted inside the hydrotheca. The modified tentacles of S. tetracythara are compared with the nematodactyls of the genus Nemalecium, with the ligula found in several sertulariid species, and with nematophores described in other thecate families. Beside remarks on species taxonomy and distribution, incitation is given to the study, with emphasis especially on hydranths.

Four valid species of the genus Gymnogonos are known at this point of investigations: G. crassicornis (northern Atlantic and the Arctic Seas); G. obvolutus (northern Atlantic and the Arctic Seas); G. ameriensis (circumantarctic distribution) and the new species G. pacificus (northern Pacific). Other species, such as Corymorpha antarctica (Pfeffer, 1889) and Tubularia cingulata (Vanhöffen, 1910) from the southern hemisphere are recognized as ‘species inquirendae’. New descriptions and taxonomic discussions of the known Gymnogonos species have been proposed. This genus has a typical bipolar distribution in the classical meaning of this term. This genus origin may rise from tropical Corymorphidae by neoteny in the period of glacial cooling.

The Council have great pleasure in reporting that Prof. A. V. Hill, C.H., O.B.E., F.R.S., was elected President of the Association in June in place of Prof. Sir James Gray, Kt., C.B.E., M.C., F.R.S., who had served for the preceding ten years.

The Council wish to record their deep appreciation of the many services rendered to the Association by Sir James Gray during his long term of office as President, and are glad to report that he will continue to serve on the Council as Governor representing the Royal Society. Sir James Gray has been elected a Vice-President of the Association.

The north-eastern Atlantic gobiid genus Lebetus Winther, 1877, was formerly believed to contain two species, Lebetus scorpioides (Collett, 1874) and L. orca (Collett, 1874). These have been subsequently shown to represent females (and immature fish) and males respectively of a single, sexually dimorphic species whose valid name is L. scorpioides. The discovery of two forms of Lebetus postlarvae, differing in meristic characters, fin growth, and pigmentation, is shown not to affect this conclusion but to suggest provisional recognition of another species, L. guilleti (Le Danois, 1913), with fewer anal fin-rays (A I/5–6) and vertebrae (25–26) than L. scorpioides (A I/7–8; vertebrae 27-29). A key and limited synonymy for the species is provided. As a possible alternative view it is suggested that relatively high summer sea-temperatures during early development of L. scorpioides in certain areas may produce the lower meristic features of L. guilleti.

Haliclona indistincta has in some respects, a typical reproductive cycle for a marine haplosclerid sponge. We suggest that oocytes originate from archaeocytes and that spermatozoa originate from choanocytes. Oocytes were first seen in November and matured as eggs by May and June. Immature spermatic cysts were identified from February and mature cysts were present in May and June only. Of the individuals surveyed that had reproductive elements present (150/200), reproductive elements from a single sex were reported in over half of the specimens (59%) but there were also many hermaphrodites (41%). Embryos were first seen in June. Larvae were distributed throughout the mesohyl and were released from the end of June to the end of July. Three mobile larval stages and fusing of sibling larvae were observed. Post-settlement stages from early settlement to the development of oscula and excurrent canals are also shown. However, some elements of the larvae (uniform ciliation and no spicules at posterior pole) are not consistent with larvae from this genus.

A new neritiliid gastropod, Neritilialittoralis, lives in a unique, intertidal, subterranean, brackish environment on Amami-ohshima Island, Japan. It lives exclusively on rubble that is embedded deeply in coarse-grained sand whose interstices are filled with a mixture of subsoil water and seawater. Empty shells of this species were also found in tide pools at the foot of limestone terraces on Okinawa Island, where a large volume of karst-related freshwater gushes out. The species is characterized by a very small, white shell and unpigmented skin. Neritilia has previously been found in freshwater streams, rivers, estuaries, and in anchialine and phreatic waters, and the present find expands its range of known habitats and has implications for the history of the invasion of freshwater by neritiliids. The spiral protoconch suggests that the larva of N.littoralis is long-lived, planktotroph and a very effective disperser, and all the individuals collected appear to be part of a panmictic population.

This communication presents the first records of mated female Loligo gahi in Falkland Island waters. In October 1993 fully mature mated female L. gahi were identified in samples taken from the commercial fishery in waters east of Lively Island, East Falkland, at depths of 145–174 m. Spermatophores were found in both the mantle cavity and buccal sites of deposition. These records, combined with past records of spent females, suggest spawning periods in late October/early November and April/May. These concur with two of the three periods of spawning suggested from previous studies of juvenile and adult L. gahi.

This paper contains a general account of about forty examples of tumours, mostly “malignant,” found in eighteen species of fishes, all of them marine except two, a Stickleback and a Gold-fish. In all these cases the affection was a very obvious one, attracting immediate attention from the fishermen who caught the specimens, or leading to condemnation of the fish by market inspectors. In some cases the appearance presented by the fish was grotesque, or repulsive in the extreme. I give a list of the specimens dealt with on p. 447–8: all these represent “cancerous” affections. Many other diseased fishes, obtained in the same ways, have been seen and examined. Malformations of development, or growth; large healing scars due to wounds; repulsive ulcers of unknown origin; parasitic tumours and two cases of undoubted piscine tuberculosis (in Cod) have also been examined. Here, however, I refer only to tumours which exhibit the character of malignancy.

Static toxicity tests (20.5 ±1°C, 24 ±2% salinity) were run to assess the toxicity of copper to the embryonic development of Scrobicularia plana (Mollusca: Bivalvia); the end point of interest was the production of D-larvae after 48 h culture. While a nominal concentration of 10 μg Cu I1 was not found to be toxic, an EC90 (concentration preventing 90% of the experimental population from achieving the end point defined) can be set at ~20 μg Cu I1. For this end point, copper is indicated to be 16 times less toxic than the antifoulant tributyltin (TBT). Moreover, copper has probably little relation with the reported recent decline of S. plana throughout northern Europe.

The spectral absorption of the violet pigment extracted from dried Ianthina secretion by acetone is described. The colour of the secretion adsorbed on cellulose tissue is reasonably stable for purposes of transport. The pigment does not appear to be identical with the bilidiene-protein pigments of Aplysia, or with other violet molluscan pigments. The pigment of Ianthina shell is not extractable with acid, and all save that of the pellicle disappears on decalcification.

We provide a review on scientific contributions concerned with Leptocaris (Harpacticoida: Copepoda) that includes the zoogeography, ecology, biology, and morphology of this genus. A tabular key is given to aid in the identification of the ignavus-group. Leptocaris ryukyuensis sp. nov. is included on the basis of specimens collected from Akeijima sandy beach of the Ryukyu Islands in Japan. The new species can be distinguished from its congeners by an abexopodal seta and 3 exopodal setae on A2, a barbed inner seta on the proximal, endopodal segment of female P1 to P3, setae of the caudal ramus (setae I and II are very small, and the basal seta is transformed to a big spine), and modified inner setules of P2 enp-2 and P3 enp-2 in the males. The new species belongs to the ignavus-group established by Kunz (1994) and is the third species of the genus Leptocaris in East Asia.

The ribosome is the location of protein translation and therefore a pivotal macromolecular complex for all organisms. The RNA molecules involved in the formation and functioning of the ribosome (rRNA) are partially single-stranded (loops) and partially double-stranded (helices or stems) as a result of pairing of complementary regions in either their own or other rRNA subunits. This pattern provides the rRNA with a secondary structure crucial for its functionality. The stability of these secondary structures is mediated by their base compositions: a helix rich in G-C pairs possesses a higher thermodynamic stability than an A-T rich counterpart. However, the base composition of these structures is neither homogeneous throughout the molecule nor throughout the demosponge taxa. Here, we present patterns of biased nucleotide composition in demosponge 28S rDNA. We analyse their correlation in respect to environment and taxonomy. We find significantly higher G+C contents in haplosclerid demosponges compared to other orders and investigate evidence for an association between water temperature and rRNA base composition in demosponges.

A Government grant by the Royal Society enabled me to spend the months of August and September of 1889, in the investigation of unknown or obscure points in the marine algæ, in the Laboratory of the Marine Biological Association, Plymouth. One of my chief objects was to obtain such material of the various members of the Gigartinaceæ, of Spyridia, Stenogramme, and other genera, as would permit me to make a detailed examination of the development of the fruit (cystoearp) from the earliest stage to maturity. Several of the genera required were very rare or of unknown locality, and in many cases only to be found by dredging. In searching for these, new weeds, or new localities for known weeds, were met with, and it seemed to me the notes I made would be of use to algologists. Cocks, Hore, Boswarva, Gatcombe, &c, and of late years Holmes, have combined in their work to give a very full account of the marine algæ to be met with without the use of the dredge. For twenty years Cocks, I am told, did not miss a single low tide at Plymouth (or, if not, Falmouth). Up to the present our knowledge of the weeds of Plymouth has been derived almost entirely from shore-hunting, some of the rarest weeds being described as washed ashore, so that it was a question as to whether such weeds were locally established or merely “drift” specimens. In 1867 Boswarva published his Flora of Plymouth Sound in the Transactions of the Plymouth Athenaeum, his catalogue being compiled from the discoveries of himself, Cocks, &c. This list appears word for word in the Marine Biological Association Journal, No. 2, 1888. I am permitted by Mr. Holmes to say that through a misunderstanding he is stated to give the names of eight additional species.