ALBERT

Description: Spirula spirula has stimulated considerable interest since it was first discovered. It is a member of one of the two genera of sepioids to frequent oceanic water (the other being Heteroteuthis); it has a unique spiral shell which acts as a buoyancy mechanism and can withstand considerable pressure (Denton, Gilpin-Brown & Howarth, 1967); and, until the capture by the Danish Oceanographical expeditions it was considered very rare, only 12 specimens having been captured. The Dana expeditions caught 193 individuals from 1909 to 1931 and these were described by Kerr (1931) and Bruun (1943,1955). Most of these were caught in the waters around the Canary Islands of the North Atlantic. Bruun (1943) arranged the specimens according to month and size and claimed that two size groups could be distinguished. The specimens were taken over a wide geographical area, in several years and during the months of February (1 specimen), March (40), April (3), May (8), June (1), August (1) and October (23). His conclusion concerning growth depends entirely upon his decision to split the March sample into two year-groups; those above 1.9 cm in ventral mantle length he put in a separate year-class to those below 1.9 cm in ventral mantle length. This division was arbitrary and, one suspects, based on a belief that a one-year life-span was likely. Clearly the growth of Spirula requires further study based on a larger collection and the present paper is an attempt to fulfil this need.

Description: Since organic chemistry began, the chemistry of natural products from terrestrial organisms such as plants and fungi has been studied intensively; in contrast, marine species have received relatively little attention. However, in the last decade research in the field of marine products has increased sbstantially. The heightened interest in this area is attested by the appearance of the monumental treatise of Halstead on Poisonous and Venomous Marine Animals in 1965 (108), Baslow’s review on “Marine Pharmacology” in 1969 (14) and Scheuer’s recent book “Chemistry of Marine Natural Products” (160) in 1973. In addition Premuzic’s review devoted to the Chemistry of Natural Products Derived from Marine Sources, was published in volume 29 of this series in 1971 (152).

Description: A single layer of cells secretes the hard cephalopod beaks. The beccublasts are tall columnar cells that separate the beak from the surrounding buccal muscles, and must serve to attach these muscles to the beak. Within the cell layer there are three types of cells. The first, and most frequently found contain cell-long fibrils. These fibrils may have contractile and tensile properties. Complex trabeculae extend from the beccublasts into the matrix of the beak. The fibrils are attached to these trabeculae and at the other end of the cells they are anchored near to the beccublast-muscle cell interface, closely associated with the muscles that move the beak. The second group of cells contain masses of endoplasmic reticulum the cysternae of which are arranged along the long axis of the cell. These cells also contain dense granules and are probably the major source of beak hard tissue. It is probable that each cell secretes its own column of beak hard tissue. The third group of cells contains a mixture of fibrils and secretory tissue. In the beccublast layer there are changes in the proportion of the three types of cells depending upon the region sampled. In the region where growth is most active there are mostly secretory cells, whereas near the biting and wearing tip there are mainly anchoring type cells.

Description: Laboratory data are presented on the distribution of cobalt between pyrite, chalcopyrite, and pyrrhotite. Pyrite-type deposits are used to show that the results enable one to estimate the temperatures of formation for copper mineralization. Recent years have seen extensive studies on element distributions between coexisting minerals in order to define mineralogical thermometers and barometers [1-3]. Detailed studies have been made of the thermodynamic basis of such distributions, as well as of the factors that influence component levels in coexisting minerals. Here we will not consider a theoretical analysis of the distribution, but we do note that trace elements appear in pyrite and chalcopyrite only below the 1 wt. % level, while the compositions of the minerals deviate only slightly from stoichiometric, with temperature the main parameter that controls the distribution.

Description: Mutterkorn, das Dauermycel des auf Roggenähren wuchernden Fadenpilzes Claviceps purpurea, enthält eine Gruppe hellgelber, schwach saurer, optisch aktiver Farbstoffe. Obwohl die ersten Präparate dieser Farbstoffe schon vor fast 100 Jahren von DRAGENDORFF und Mitarb. (14) isoliert wurden, konnte deren Strukturaufklärung im wesentlichen erst in den letzten Jahren durchgeführt werden. Dies ist darauf zurückzuführen, daß für die Reindarstellung der schwer trennbaren, teilweise diastereomeren Farbstoffe leistungsfähige chromatographische Methoden entwickelt werden mußten (1, 27, 29, 47). Als sich gezeigt hatte, daß diese Farbstoffe eine Naturstoffgruppe aus mehr als 10 Vertretern mit sehr ähnlichen Strukturen bilden, wurde für sie der Sammelname Ergochrome und eine einfache Nomenklatur vorgeschlagen (19, 25, 29).

Description: The distinguishing features of the common squid of British waters, Loligo forbesi, are summarized, and contrasted with those of L. vulgaris. The life-cycle and growth of L. forbesi are described, based on samples from trawl catches off Plymouth. This species seems to be an annual - young squid first appear in the trawl in late May, when their length is about 10 or 11 cm. Subsequent growth is rapid, and the males reach 30 cm and the females 25 cm by November. Spawning takes place mainly in December-January, but may continue into the spring. Neither sex survives beyond a single spawning season. Hatching of the spawn probably takes 30–40 days, and if the young squid taken in the trawl in late May hatched in the early part of the same year, a growth rate of about 25 mm/month would be required. Known growth rates for other species of Loligo are about 20 mm/month, so that indicated for L. forbesi does not seem to be impossibly high. The life-cycle is summarized in Fig. 8. There is also a summer spawning population, which grows to a rather smaller size at maturity, and which also seems to be annual. During the summer L. forbesi ranges throughout the English Channel and southern North Sea, particularly in inshore areas. In October the squid migrate farther offshore and tend to occupy the western part of the Channel. Values for total weight of squid/2 h trawl are given, on a monthly basis, for 1966–9. The largest quantities are usually taken in October and November, the highest single figure being 30.54 kg/2 h trawl, in November 1967.

Description: Twenty-four out of 240 fishes caught by bottom lines at 366–3333 m had something in their stomachs. Stomach contents included parts of cephalopods, fish, cetaceans and bottom-living invertebrates, thin rubber sheet and terrestrial mammal bones. The material provides evidence that four species of cephalopod are at least partially demersal and suggests a means by which the tapeworm Phyllobothrium could pass from its secondary to its primary host. During the five biological cruises of R.R.S. ‘Discovery’ between 1967 and 1971 a total of 31 bottom lines with 1483 hooks were fished in depths of water between 366 and 3333 m. The stomachs of the 240 fish caught were examined and 216 (90%) proved to be empty. The high incidence of empty stomachs is thought to be due to frequent loss of food during the ascent from great depths and accounts for our poor knowledge of the feeding habits of demersal fish living at depths exceeding 400 m. The present collection of food from 25 stomachs (24 from ‘Discovery’ collections and one from a fish caught by Mr G. R. Forster from R. V. ‘Sarsia’) of fish belonging to 11 species (Table 1) probably gives little indication of the usual diet of the fish concerned, but its nature prompts some useful speculation and the rarity of such observations justifies placing them on record (Bigelow & Schroeder, 1948; Marshall, 1954). All the fish were caught on lines which lay on the bottom for several hours and it is our firm belief that they were hooked while on or very near the bottom.

Description: The bottom sediments of Sörfjord, West Norway, contain unusually high concentrations of Ag, Ba, Bi, Cd, Cu, In, Pb, Sb, Sn, and Zn. The concentrations of Zn and Pb reach ∼ 10% by weight in some sediments. The concentrations of most of the elements are positively correlated, those of Pb, Cd, and Cu with Zn being particularly well developed; correlations also exist between Sb and Zn, and Ag and Cu. The concentrations of the metals in the bottom sediments decrease southwards and northwards from a locality close to a source of industrial waste.

Description: The ommastrephid squids are large active animals occurring in most of the world's oceans. Luminous organs or bioluminescence have been observed only in members of the subfamily Sthenoteuthinae, containing the genera Ornithoteuthis, Symplectoteuthis (= Eucleoteuthis), Hyaloteuthis, Ommastrephes and Dosidicus. The light organs of Ommastrephes pteropus are small sub-spherical bodies randomly distributed over the ventral surface of the mantle, head, arms and tentacles (Roper, 1963) and are aggregated dorsally to form a large luminous patch (Clarke, 1965). Relatively little is known about the organs, capabilities and biochemistry of luminescence in cephalopods (Harvey, 1952; Herring, in Press), and the size of the light organ and availability of O. pteropus provide an unusual opportunity for such studies. Although among the molluscs the luminescent systems of the gastropod Latia and the bivalve Pholas have been partially characterized (Shimomura & Johnson, 1968; Henry, Isambert & Michelson, 1970, 1973) the only cephalopod system which has been investigated to date is that of the enoploteuthid Watasenia scintillans (Goto et al., 1974; Inoue et al., 1975). This investigation examines the anatomy and biochemistry of the dorsal light organ of O. pteropus, which differs markedly in these respects from the brachial organs of Watasenia.

Description: Squids (teuthoids) fall into two distinct groups according to their density in sea water. Squids of one group are considerably denser than sea water and must swim to stop sinking; squids in the other group are nearly neutrally buoyant. Analyses show that in almost all the neutrally buoyant squids large amounts of ammonium are present. This ammonium is not uniformly distributed throughout the body but is mostly confined to special tissues where its concentration can approach half molar. The locations of such tissues differ according to the species and developmental stage of the squid. It is clear that the ammonium-rich solution are almost isosmotic with sea water but of lower density and they are present in sufficient volume to provide the main buoyancy mechanism of these squids. A variety of evidence is given which suggests that squids in no less than 12 of the 26 families achieve near-neutral buoyancy in this way and that 14 families contain squids appreciably denser than sea water [at least one family contains both types of squid]. Some of the ammonium-rich squids are extremely abundant in the oceans.

Description: The effect of medium dissolved-oxygen tension on the molar growth yield, respiration and cytochrome content of Beneckea natriegens in chemostat culture (D 0·37 hr-1) was examined. The molar growth yield (Y), the specific rate of oxygen (qo2) and glucose consumption, and the specific rate of carbon dioxide evolution were independent of the dissolved-oxygen tension above a critical value (〈 2 mmHg). However, the potential respiration rate increased with reduction in the dissolved-oxygen tension at values of the dissolved-oxygen tension well above the critical value. Changes in the cytochrome content occurred at dissolved-oxygen tensions well above the critical value. An increase in cytochrome c relative to cytochrome b was observed as the dissolved-oxygen tension was decreased. Reduction of the dissolved-oxygen tension to less than 1 mmHg caused a switch to fermentative metabolism shown by the apparent rise in Y o2 and decrease in the molar growth yield from glucose. At this point the potential respiration rate (q o2) increased to its highest value, while the cytochrome pattern reverted to that observed at dissolved-oxygen tensions above 96 mmHg. There appeared to be no correlation between cytochrome content, potential q o2, in situ q o2, and cyanide sensitivity of the organism at various dissolved-oxygen tensions.

Description: The asymmetry of the continental margin around southern Africa can be related to Mesozoic sediment thicknesses, which were in turn controlled by the local structural setting. On the west coast, the Orange Basin sediments were built out as a thick wedge over the margin of the continent by discharge from the Orange River, whereas on the Agulhas Bank, sedimentation was confined to continental areas. Off the east coast the extremely narrow margin of the continent did not form an effective trap for sediments, which were readily carried beyond it. Cainozoic sediments are thin, and modify the Mesozoic sediment pile only locally on the outer shelf and slope.

Description: Enrichment cultures were prepared with different media for phototrophic bacteria from four species of marine sponges, collected from oxic coastal waters near Split (Yugoslavia). We obtained pure cultures of six strains of Chromatiaceae and two strains of Rhodospirillaceae by agar shake dilution. The Rhodospirillaceae were identified as Rhodopseudomonas sulfidophila and a marine form of Rhodopseudomonas palustris. TheChromatiaceae were identified as Chromatium vinosum, Chromatium gracile, Chromatium minutissimum. Ectothiorhodospira mobilis, and a Chromatium species, which in some respects resembles Chromatium minus. The occurrence of strictly anaerobic phototrophic bacteria in aerobic sponges is discussed with respect to nutrition and possible syntrophism

Description: Processes from above and below influence the sea bottom and its sedimentary cover. The evolution of the lithosphere is being as passionately discussed today as was the evolution of the biosphere a century ago. The physical, chemical and biological interactions at the sea bottom, of "benthic boundary", call for interdisciplinary research.

Description: Three species of Foraminifera, which were ususally regarded as members of the Ammonia beccarii (L.)-group or closely related, are investigated. The material comes mainly from the lagoon of Cochin and from the shelf off Cochin (SW-India), Malabarcoast). Sections and Stereoscan-microphotographs revealed considerable differences in the internal structure (double or simple septae, different shape of the tooth-plates, areal or interiomarginal situation of the septal apertures). This leads to the conclusion, that only one species (Rotalia beccarii var. sobrina SHUPACK 1934) is a true Ammonia. Rotalia beccarii var. tepida CUSHMAN 1926 should be put to the genus Discorbis, Rotalia pauciloculata PHLEGER & PARKER 1951 is regarded as a species of Pseudoeponides. Some ecological observations are added.

Description: A new bacteriochlorophyll b containing phototrophic bacterium was isolated from extremely saline and alkaline soda lakes in Egypt. Enrichment and isolation were performed using a synthetic medium with high contents of sodium carbonate, sodium sulfate and sodium chloride. Photoautotrophic growth occurred with hydrogen sulfide as photosynthetic electron donor. During oxidation of sulfide to sulfate extracellular elemental sulfur globules appeared in the medium. Cells were also capable to grow under photoheterotrophic conditions with acetate, propionate, pyruvate, succinate, fumarate or malate as carbon sources and electron donors. Under these conditions sulfate was assimilated. Optimal growth under the applied experimental conditions occurred at a total salinity of 14–27%, a pH-range between 8.1 and 9.1 and a temperature between 47°C and 50°C. The cells were 0.5–0.6 μm wide and, depending on cultural conditions, 2.5–8.0 μm long; they were spiral shaped, multiplied by binary fission and were motile by means of bipolar flagella. Intercytoplasmic photosynthetic membranes were present as stacks. Bacteriochlorophyll b was the main photosynthetic pigment; small amounts of carotenoids were mainly present as glucosides of rhodopin and its methoxy derivative. The new organism is described as Ectothiorhodospira halochloris.

Description: Data presented and discussed here were collected continuously during April/May 1975 in the Bornholm Basin of the Baltic Sea. Sedimentation rates of particulate matter were recorded with 5 multisample sediment traps from different depths in the water column at 2 positions 170 km apart. Current meter data collected during the same period and depths indicated that the positions remained hydrographically distinct during the investigation. Particulate matter from the euphotic zone including diatom cells formed the bulk of the material collected by all traps. This flux of organic particles to the bottom was unimpeded by the strong density stratification present in the water column. The upper traps always collected less material than lower ones. This paradox has been ascribed to diminishing current speeds with depth, concomitant with an increase in sinking rates of phytoplankton and phytodetritus. Both factors influence the sampling efficiency of sediment traps, which are thought to have underestimated actual sedimentation rates here. A time lag of 2 to 3 weeks in bloom development seemed responsible for the characteristic differences between the two positions. The phase of major sedimentation at one position covered about 18 days, and a distinct sequence in the composition of the material collected by the 6 glasses of each trap indicated phases of a progressively deteriorating phytoplankton population in the water column contributing the particulate material. A total of 6.2 g C m-2 in 34 days was recorded at this station. Apart from a trap situated in an oxygen deficient layer which collected 0.44 g C m-2 of zooplankton corpses, zooplankton mortality was overestimated by the traps. Large-scale sedimencation of “fresh” organic matter produced by the spring bloom is probably a regular feature in areas with low over-wintering zooplankton populations and, as such, possibly has a direct stimulatory effect on growth and reproduction of the benthos.

Description: A new method is proposed for determining absolute surface water paleotemperatures by means of Globigerina bulloides d’Orbigny. This method is based on the relationship between the percentage of sinistral specimens in a population of the species mentioned and the temperature of the water. The advantages and disadvantages of the method proposed are discussed.

Description: Terms, dimensions and ratios for statolith description are defined. The form of the calcareousstatoliths in the Teuthoidea, Sepiodea and Octopoda is described by reference to Loligo forbesi, Sepia officinalis and Eledone cirrosa. While statoliths change in form and size during the growth of a cephalopod, the adult form is often characteristic for a species, despite some variation. Description of statoliths is important in studies of the fossil remains of cephalopods lacking calcareous shells, and will probably become important in the taxonomy of living species, in food analysis of cephalopod predators and in the study of deep sea deposits.

Description: Eighty-seven specimens of Bathothauma lyromma from the ‘Discovery’ collections have provided new information on this unusual species. The size range represented is sufficient to trace the development from small larvae to near adult. Information on sexual development is also given. Twenty-nine specimens from opening-closing nets show that Bathothauma occupies the depth range 100–1250 m, with smaller specimens living at shallower depths than the larger ones.

Description: A female blue-ringed octopus, Hapalochlaena sp. (probably lunulata), was maintained in an aqarium for nearly 3 months, during which time it spawned and cared for the eggs until hatching. The young are planktonic. Embryonic development does not differ markedly from that observed in other octopods, uniting certain features of the development of Octopus vulgaris and Eledone cirrosa. In terms of reproductive biology and development, the species differs from the lesser blue-ringed octopus Hapalochlaena maculosa in its mode of spawning, egg size and mode of life of its young. These differences correspond to conditions recorded for Octopus spp. and Eledone spp.

Description: Shipworms or Teredinidae may be dispersed either as adults in floating wooden objects or as pelagic larvae drifting near the sea surface. Five shipworm species, i.e., half of those having an amphi-Atlantic geographical distribution, are known also to have pelagic phytoplanktotrophic larvae which can be carried by ocean currents. From a series of 742 plankton samples taken from throughout the temperate and tropical North Atlantic Ocean, it can be shown that shipworm larvae are not uncommon in the open sea. Teredinid veligers were found in 19% of all samples taken. One species of larvae, identical in all details to that described by Rancurel (1965), is particularly prevalent and is tentatively identified as Teredora malleolus (Turton). A definitive identification will be possible only after the pelagic larvae of the other Atlantic species are known. The larvae of Teredora malleolus are found throughout the North Atlantic Gyre and the adjacent temperate and tropical seas, and from scattered records in the South Equatorial Current. Larvae of other unidentified Teredinidae species were also found. The distance that larvae may be transported depends upon the length of pelagic larval development and the velocity of the currents. From the known current velocities it can be shown that, even in a few weeks, larvae may be dispersed many hundreds of kilometers. The geographical distribution of shipworm larvae suggests that they are carried along the coasts of continents and even across ocean basins, and that this dispersal must be an important factor in the geographical distribution of the adult forms and in the maintenance of genetic continuity between populations otherwise isolated from one another.

Description: Deep sea sediments contain more Cu, Ni, Ba, B etc., than transport of detrital terrigenous matter (TM) can explain. Longdistance transport in dissolved from is of no importance for many of these elements. Marine biological matter (BM) is enriched in Cu, Ni, Ba, B etc. Conservative mixing models, using BM and TM as inputs show that the compositional variations in pelagic sediments can be explained by these sources. Such mixing models have been used to estimate how the influx of BM and TM have varied with time, and to what extent different elements ares upplied by BM and TM. The results show that in Cenozoic Equatorial Pacific sediments CaCO₃, opaline silica, B, Ba, and Cu are predominantly biogenous. It is probable that also P and Ni belong to this group of elements, whereas almost all Al, Ti, Zr, V and Mn are delivered by TM or some volcanic processes. The accumulation rates (AR) for the biological constituents reached maxima during the L. Oligocene and the Miocene, and minima during the U. Oligocene and the Pleistocene; some AR from the Oligocene and the Miocene being 3-6 times higher than at present. The accumulation rate patterns for opaline silica, Ba and B co-vary, whereas the AR for CaCO₃ show another time dependance pattern. These AR-patterns are probably partly due to climatic variations. Plankton in Pacific Equatorial waters incorporate much more Cu, Ni, etc., than is required for the particulate transport of these elements to the ocean floor. This suggests that transport in particulate form of BM is an important source of Cu, Ba, B, etc. for the deep sea floor.

Description: A total of 618 cephalopods comprising 29 identified species and 98 young unidentified larvae were collected at 30° N 23° W in opening–closing rectangular midwater trawls (RMT combination net), an Isaacs Kidd midwater trawl equipped with an openingclosing bucket and a British Columbia midwater trawl. Discrete horizons were fished between the surface and 2000 m and day and night vertical distribution for the more common species is described. Material is sufficiently abundant to draw tentative conclusions on the vertical distributions of 16 species. These show a wide variety of migratory and non-migratory behaviour including diel migration, ontogenetic migration and static distribution at various depths and over various depth ranges.

Description: Little work on vertical distribution of cephalopods was possible before the development, in the 1960s, of sophisticated opening-closing devices usable on midwater trawls such as the 10 ft Isaacs Kidd trawl (IKMT; Foxton, 1963; Aron et al. 1964) and the series of rectangular midwater trawls developed by the Institute of Oceanographic Sciences (previously the National Institute of Oceanography) (Clarke, 1969 a; Baker et al. 1973). These developments have resulted in three papers on vertical distribution of cephalopods in the North Atlantic (Clarke, 1969 ft; Gibbs & Roper, 1970; Clarke & Lu, 1974) and one for the Mediterranean (Roper, 1972). The present paper describes the vertical distribution of cephalopods caught at 40° N 20° W, 53° N 20° W and 60° N 20° W in the North Atlantic based upon day and night series of horizontal hauls between the surface and 2000 m using the RMT combination net (Baker et al. 1973).

Description: The present work is part of an analysis of catches made with rectangular midwater trawls (RMTs) in the North Atlantic at about 20°W and at 60°N, 53°N, 40°N (all in Lu & Clarke, 1975), 30°N (Clarke & Lu, 1974), 18°N and 11°N (Lu & Clarke, 1975). The collections were made for the ecological programme of the National Institute of Oceanography, Wormley, England (now part of the Institute of Oceanographic Sciences).

Description: This is one of a series of four papers dealing with vertical distribution of cephalopods in the North Eastern Atlantic at six stations near 20° W and at about 10° intervals from 60°N to 11° N (Clarke & Lu, 1974, 1975 a; Lu & Clarke, 1975). The present study is based upon a series of hauls made at discrete horizons between o and 2000 m with opening-closing nets during both daylight and darkness. The collections were made for the ecological programme of the National Institute of Oceanography, Wormley, Surrey, England (now part of the Institute of Oceanographic Sciences).

Description: Several tissues (e.g. kidney, blood, digestive gland) in oceanic cephalopods which do not exhibit in vivo bioluminescence, luminesce when homogenized in the presence of air or when simply exposed to air in a vial (blood). The source of the luminescence appears to be a luciferin: treatment of kidney homogenates and blood with a photophore extract presumably containing luciferase resulted in a 20-fold increase in light production. Luminescence was also found in the renal fluid, which may be the source of luminescent clouds produced by squids. The variability in luminescence found in some tissues of cephalopods appeared to be related to feeding. Luminescence was also detected in the digestive glands of midwater octopods.

Description: The means of detecting downwelling light for counterillumination in several midwater animals has been examined. Eyes and extraocular photoreceptors (drosal photosensitive vesicles in the enoploteuthid squid Abraliopsis sp. B and pineal organs in the myctophid fish Myctophum spinosum) were alternately exposed to overhead light or covered by a small opaque shield above the animal and the bioluminescent response of the animal was monitored. Covering either the eyes or the extraocular photoreceptors resulted in a reduction in the intensity of counterillumination. Preliminary experiments examining the bioluminescent feedback mechanism for monitoring intensity of bioluminescence during counterillumination in the midwater squid Abralia trigonura indicated that the ventral photosensitive vesicles are responsible for bioluminescent feedback.

Description: Two new species of cranchiid cephalopod are described. These were both collected by opening-closing midwater trawls (RMTs) when vertical series were fished in the North Atlantic from R.R.S. ‘Discovery’.

Description: Infrared and Mössbauer spectroscopy show that the extent of the reduction of nontronite is dependent on the chemical composition of the nontronite and on the nature of the reducing agent. Hydrazine reversibly reduces about 10% of the iron in all of the nontronites studied irrespective of composition and it is suggested that the resulting ferrous iron occurs only in distorted octahedral sites. Similar conclusions are reached for the dithionite reduction of the nontronites containing little tetrahedral iron, but for those with more than one in eight silicons replaced by iron, changes brought about by dithionite treatment are irreversible due to dissolution of appreciable quantities of iron. Results from both spectroscopic techniques suggest that iron in tetrahedral sites is preferentially dissolved and that up to 80% of the structural iron can be reduced. Evidence is presented for the formation in these extensively reduced nontronites of a small amount of a mica-like phase resembling celadonite or glauconite, and, as dithionite is used for the pretreatment of soils, the implication of this observation is briefly discussed. The use of deuterated hydrazine as a reducing agent has enabled the nontronite absorption band near 850 cm-1 to be assigned to a Si-O (apical) stretching vibration, which is inactive in the infrared for perfect hexagonal symmetry, but which is activated by distortions in the tetrahedral layer

Description: The identity of substrate-inhibitor specificity with respect to several choline esters and organophosphorus compunds was demonstrated for the cholinesterases of the optical ganglion of the squid Ommastrephes bartrami, inhabiting the South Atlantic and the Great Australian Bight. Two cholinesterases with different properties were found in optical ganglia of these squid.

Description: A technique for rearing the loliginid squids Sepioteuthis sepioidea and Doryteuthis plei is reported. Specimens of the former were reared from eggs to sexually mature adults, and maintained for a maximum of 146 days; adult D. plei were maintained for 38 days. Choice and quantity of food was most important for the survival of all sizes, particularly young squid. Newly hatched specimens thrived on Mysidium columbiae. Both species fed at a rate of 30 to 60% of their body weight daily; starvation occurred when intake fell below 10 to 15%. Food conversion efficiency averaged between 10 to 20%. Growth was rapid and steady. S. sepioidea grew to a maximum of 105 mm and 77 g in less than 5 months; D. plei grew an estimated 20 mm/month. Experimental data indicate a lethal minimum salinity for both species at about 27‰. Lethal minimum and maximum temperatures for young S. sepioidea are 17.5° to 18.0°C, and 32.5° to 33.0°C, respectively. Young consume 0.64μl O2/mg wet weight/h. Opaque tanks, with a semi-natural bottom substrate and special ultra-violet (UV) illumination, are advantageous for rearing and maintenance.

Description: Analyses of bottom trawl samples and feeding experiments in the laboratory revealed a reproduction period ranging from late March to early August in Eledone cirrosa of the Catalonian Sea (Western Mediterranean). The embryonic development, studied for the first time on eggs laid in the laboratory, shows no basic difference from that of other Octopodiae. The newly hatched animals are planctonic; Morphologically, this feature is expressed by a relatively small arm-length.

Description: Five species of Sepiola were reared in the laboratory from egg to adult size. Spawning was achieved in 3 species of Sepiola afteer 5 to 7 months. The growth rate of the species reared did not depend upon temperature, which ranged from 12,5° to 20°C. A fairly constant size increase (2,5mm mantle length/month) was observed in Sepiola during the 5 months after hatching. In Sepietta, the same growth rate was observed until the fourth month after hatching, when it increased to the rate of 5 mm mantle length/month.

Description: The problems of reproduction of Octopus vulgaris and the seasonal distribution in the sea of planctonic larvae, benthonic juveniles and adults are discussed. The influence of environmental factors on growth is shown by experimental studies in the laboratory, and the difficulties of interpreting field data are emphazised.

Description: Mineral resources on and beneath the seafloor are briefly reviewed and the present and future economic value of specific mineral resources is discussed. The results obtained from the cruises of the German research vessel "Valdivia" during its first three years of operation are presented.

Description: Calcium carbonate in sediments can greatly effect the engineering properties of those sediments. Factors that may effect engineering properties are: 1) great variation in primary void ratios, (2) inherent strength of carbonate grains, (3) degree of sorting, (4) ratio between grains and matrix, (5) nature and amount of cement, and (6) depth of burial. Deep-sea carbonates appear to be anomalous but do exist in rather large quantities. Their existence must depend upon a combination of physico-chemical and organic-chemical factors that need to be investigated in much more detail.