The fact that Spirorbis spirorbis (= S. borealis) has a summer breeding season during which several successive broods of larvae are produced has been known since the work of Garbarini (1933,1936). A recent summary of the taxonomy, ecology and distribution of S. spirorbis has been given by Knight-Jones & Knight-Jones (1977). The two aspects of the species' reproductive biology which have received most attention are the role of sea temperatures in initiating breeding and the correlation of brood production with lunar and tidal cycles. In the present work a study has been made of gametogenesis as well as of the more easily observed cycle of brood production. The results obtained have indicated, in respect of one population of S. spirorbis at least, the need for a major re-assessment of earlier studies of the species.

Giesbrecht (1895) was the first to report that the luminescence produced by marine copepods was produced by certain ‘skin glands’. In Pleuromamma abdominalis he described specific sub-cuticular cells which were responsible for the production and secretion of luminous material; such cells always contained a greenish-yellow secretion whilst non-photogenic cells were colourless. The only published histological study of luminous cells in copepods is that by Clarke et al. (1962). These authors reported numerous paired cells in the head of Metridia longa, each pair opening through a common pore, the distribution of which was correlated with areas of fluorescence. Clarke et al. (1962) further showed that the cells in each pair had different staining characteristics, and suggested that each of the two cell types produced a different component of the luminescent system, proposed as ‘luciferin’ and ‘luciferase’ respectively. They hypothe-sized that when stimulated, each cell secreted its contents, generating light as the materials combined in the surrounding seawater. Although there has been much work carried out on the physical characteristics and kinetics of copepod luminescence (e.g. David & Conover, 1961; Clarke et al., 1962; Barnes & Case, 1972; Bityukov & Evstigneev, 1982; Herring, 1983, 1988; Evstigneev, 1983, 1984, 1986; Latz et al., 1988) there is still little known of the comparative distribution of luminous cells in a range of copepod species, and even less is known of their detailed structure.

Records of the squid (Loligo forbesi) egg masses which were incidentally caught in demersal trawls at three offshore sites are presented. These sites were at water depths of 135, 302 and 507 m. This represents the deepest ever record of spawning in a loliginid squid species. There has been speculation in the literature about offshore spawning in L. forbesi but it has not previously been recorded and may have important implications for the life cycle.

Egg masses of Loligo forbesi were encountered for the first time from a depth of 730 m at Gökova Bay (southern Aegean Sea), extending the known spawning depth in the Mediterranean Sea.

A specimen of the red mullet (Mullus surmuletus L.), caught in Plymouth waters in October 1949, was found to have tumours projecting externally on the pectoral fins. They were spherical or elliptical in shape, the largest being 20 mm. long. On the suggestion of Mr G. A. Steven some of these outgrowths were cut out and given to the writer for microscopic examination.

When examined fresh they appear to consist of small, spherical, cyst-like bodies of various diameters, but there was no obvious clue as to their nature. After fixing in Bouin and sectioning, they are seen to be composed of cells of various sizes (PI. I, figs. 1–4). It can be seen that these cells lie close to one another, leaving only a little space for the embedding connective tissue which is characterized by the abundance of its own small cells. The blood vessels met with in this tissue contain fish erythrocytes. The whole is covered by stratified squamous epithelium (PI. I, fig. 2).

The material on which the present report is based was collected by the Oithona from 1906 to 1909 inclusive, and during the latter half of 1913. Attention was directed particularly to the capture and determination of the post-larval fishes. The investigations during the first four years were carried out by Mr. A. E. Hefford, and his notes have been fully relied upon for the identification of the species. For the collecting and working out of the 1913 material I am directly and wholly responsible.

Oceanic juvenile loggerhead sea turtles, Caretta caretta, foraging in Azorean waters, are incidentally caught in drifting longlines that target swordfish, Xiphias gladius, and blue shark, Prionace glauca. Data were recorded during a longline gear modification experiment conducted in 2000. The results show that the captures are not uniformly distributed in relation to fishing effort, with 81% of the loggerheads (N = 232) caught in one-third of the sets (N = 93). The highest turtle catch rates were around the eastern group of islands, an area characterized by the presence of mesoscale eddies induced by bathymetric features. High catch rates coincided with the presence of the thermohaline front, between August and October, and when targeting blue shark. To investigate the causes of these differences we fitted a general linear model to evaluate the influence of mean depth, minimum depth, sea surface temperature (SST), soak area, soak time, moon phase and wind force on turtle and target species catch rates. These results revealed that mean depth and SST were most important for loggerhead catch rates, while minimum depth was the only significant variable for swordfish and mean depth, SST, wind force, moon phase and soak time influenced blue shark catches. The distribution of loggerhead sea turtles can be predicted by monitoring fishing areas in relation to bathymetry and SST. The impact of longline fishing could be greatly and quickly reduced by regulating the blue shark fishery and by increasing fishermen awareness for sea turtle conservation.

The effects of trampling are usually confounded by the diffuse impacts of the urbanization of sandy beaches. We performed a controlled experiment on a beach with low visitation rates to test the hypothesis that ghost crabs avoid building their burrows on impacted plots as a result of the compacted sediment, and they migrate to non-trampled areas. The sampling design encompassed 11 survey quadrats (6 × 6 m) above the strandline, including five trampled plots (100, 300, 900, 1500 and 3000 steps) and six non-trampled plots. The plots were sampled before and after 24, 48 and 72 h of experimental trampling. We found that the ghost crabs avoided building their burrows in only the 1500× and 3000× trampled plots after 24 h, but the avoidance was not related to sediment compactness. Additionally, the emersion time and escape distance from humans were significantly delayed in the most trampled plots, suggesting a lower surface activity and an avoidance of irregular (i.e. high micro-relief) sediment surfaces by ghost crabs, which might reduce their ability to perceive potential predators.

Morbihan Bay, France, is an important spawning area and nursery grounds for young cuttlefish. The eggs and the young cuttlefish are subjected to predatory species of fish. These were identified by analysing the stomach contents of 26 species and two species of cephalopods. Five fish species were found to be predators of young cuttlefish. The Balistes carolinensis feeds on the eggs, and Dicentrarchus labrax, Labrus bergylta, Spondyliosoma cantharus, and Conger conger eat young cuttlefish, from 8 mm (hatching cuttlefish) to 61 mm in mantle length (cuttlefish about 4-months old).

A new species of Chrysochromulina Lackey with exceptionally long cylinder-scales distributed evenly over the cell is described and illustrated with electron micrographs of shadowcast whole mounts of wild material from the Galapagos Islands, South Africa and the English Channel. In all cells, the cylinder-scales are underlain and outnumbered by highly characteristic plate-scales, each with a conspicuous infra-marginal ridge on the distal face. Some consistent dimensional and other differences between periplasts from Africa and the Galapagos Islands are noted, with the British equivalents approximating more closely to the former though with minor differences from both. The observations are interpreted in a preliminary way, but further comment including comparisons with other taxa will follow.

The difficulty of keeping planktonic organisms alive in captivity has greatly hindered experimental studies of their physiology and behaviour. This has especially been the case with the plankton of the deep sea. Up to the present our studies of these organisms have been largely morphological and distributional and it is clear that to learn more about their ecological relationships we must find means of keeping them alive to study their metabolism and behaviour experimentally. With this end in view attempts have been made to keep some oceanic plankton animals alive in the laboratory on board ship and ashore.

Three sightings of Mesoplodon beaked whales are reported from the Bay of Biscay, north-east Atlantic. All sightings comprised one or two animals, breaching repeatedly in proximity to the survey vessel, and occurred at between 2200 and 4100 m water depth. Descriptive and photographic data are compared with published accounts of Mesoplodon species in the north-east Atlantic, and the identification of the animals as True's beaked whale (Mesoplodon mirus) concurs with all observed features. Within the north-east Atlantic, True's beaked whale is the only Mesoplodon species that could produce the single, closely-spaced parallel-paired scar observed on one animal. Our observations are consistent with the first live sightings of True's beaked whale in the Bay of Biscay, and only the second documented record worldwide.

Morphometric measurements were collected on red porgy, Pagrus pagrus, red seabream, Pagellus bogaraveo, and common dentex, Dentex dentex samples, from four countries along the south European Atlantic coast and the Mediterranean Sea (Portugal, Spain, Italy and Greece). Multivariate statistical analysis was used to discriminate populations. Stepwise discriminant analysis yielded a reduced variable set that identified significant differences among all four countries. The overall per cent-correct classification rate for the four samples from the stepwise discriminant analysis, based on 18 adjusted morphometric characters for Pagrus pagrus samples, and 14 (for both Pagellus bogaraveo and D. dentex) samples were 99·6%, 100% and 97·9%. There was a significant degree of morphological dissimilarity between countries (samples), for each species. A clear difference was displayed between the Atlantic and the Mediterranean samples, and a geographical gradient was found for the common dentex.

The analysis of data on replicate vertical plankton hauls gives a value of the order of 35 % for the coefficient of variation of a single observation for a haul of moderate length. The results are similar to those presented by Winsor & Walford (1936), and Winsor & Clarke (1940); and are not at variance with the suggestion that the animals are randomly distributed, and that the variations obtained are largely dependent upon variation in the volume of water filtered by the net.

Nicothoë astaci is a choniostomatid copepod (Gurney, 1929) parasitic on the gills of the lobster, Homarus vulgaris Milne Edwards. In view of the possible effect of Nicothoë on the lobster, which is of considerable commercial importance in Scotland, a programme of work was instituted on the biology of the parasite.

Nicothoë attaches itself by means of its suctorial mouth to a gill filament of the lobster, and the wall of the filament is pierced by the sharp, styliform mandibles. The host's blood is sucked by means of a muscular gullet leading to the stomach. Nicothoë often occurs in groups, especially near the bases of the gills. The adult parasite is incapable of any movement except a slight lateral displacement of the abdomen and, once attached, probably remains in the same position throughout its life. Little is known of the life cycle, and all individuals so far definitely recognized have been females.

The rapid growth of bacteria when sea water is stored in glass vessels, and the possibility that this is brought about by the concentration of food by adsorption on the solid surface, are discussed. Some evidence is presented bearing upon such adsorption.

The regeneration of phosphate from dissolved organic phosphorus compounds in the sea and in stored water is considered.

In the second paper of this series (Carlisle, 1959 b) I have described the results of various experimental manipulations upon the termination of the male phase in the protandric hermaphrodite Pandalus borealis Krøyer. In this paper I shall be concerned with the effects of such interference upon the initiation of the female phase of the life history.

Whilst evaluating the use of RoxAnn® for benthic biotope mapping it was noted that over certain visually similar sediments differences were observed in the acoustic signature. To assess this phenomenon a number of physical parameters were determined (mean sediment grain size, sediment sorting, sediment organic carbon content and the percentage of sand, silt and clay present in the substratum) from within a survey area in the North Minch. Investigation of the epifaunal and burrowing megainfaunal communities was also carried out using towed underwater television (TV) techniques. Generalized linear modelling showed that changes in Nephrops norvegicus burrow density could account for 94·7% of the variability in the RoxAnn® E1 signal. The model, however, appeared to be improved when both the percentage of silt present and the sorting of the sediment were also taken into account, with 984% of the variance in El being explained. Although improving the original model, the addition of these extra variables was, however, considered insignificant in terms of the variability accounted for by N. norvegicus density alone. The findings of this study are discussed in relation to possible shellfish management.

The population genetic structure of the mantis shrimp, Oratosquilla oratoria, in Hong Kong waters was determined using 923 base pairs of mitochondrial DNA control region sequences. Samples were collected from six localities including the open-waters and sheltered bays in both the eastern and western waters of Hong Kong. Twenty-seven haplotypes were detected in 99 individuals. A high overall haplotype diversity (h = 0.886), with a low nucleotide diversity (π = 0.0026), was observed, and the haplotype minimum spanning network suggested that rapid expansion might have occurred among the total stomatopod population. Genetic homogeneity was observed over a meso-scale distance (80–100 km) whilst there were significant genetic differentiations between all pairs of the six samples. Partition of genetic variability based on hydrographic conditions did not reveal significant differentiations between: (1) eastern and western waters; and (2) open-waters and sheltered bays; but showed high levels of variation both within groups and within samples. Unexpectedly, genetic distance did not correlate with hydrographic distance among the samples. Results demonstrated a genetic patchiness pattern of O. oratoria in Hong Kong waters that may be attributable to the interplay between hydrographic conditions (e.g. salinity) and the species' life history traits.

The species was first distinguished by Carmichael, as Ceramium acanthonotum, in his unpublished Algae Appinensis, the manuscript of which is now preserved at the Herbarium of the Royal Botanic Gardens, Kew. Harvey (in Hooker, 1833), in publishing Carmichael's description, regarded the species merely as a variety of C. ciliatum. Agardh (1844) raised the variety to specific status, and it is as C. acanthonotum that the species has been known generally. Kiitzing (1841), 1 in a revision of the genus Ceramium, had described the entity independently as Acanthoceras shuttleworthianum; the specific epithetshuttleworthianum has priority overacanthonotum [see Article 60 of the International Code of Botanical Nomenclature (Lanjouw, 1956)]. The priority of the epithet shuttleworthianum was indicated, independently, by both Silva (1959) and Dixon (1959); of the two publications, that by Silva is the earlier.