ALBERT

Description: Bacteria use quorum sensing to orchestrate gene expression programmes that underlie collective behaviours. Quorum sensing relies on the production, release, detection and group-level response to extracellular signalling molecules, which are called autoinducers. Recent work has discovered new autoinducers in Gram-negative bacteria, shown how these molecules are recognized by cognate receptors, revealed new regulatory components that are embedded in canonical signalling circuits and identified novel regulatory network designs. In this Review we examine how, together, these features of quorum sensing signal–response systems combine to control collective behaviours in Gram-negative bacteria and we discuss the implications for host–microbial associations and antibacterial therapy.

Description: Dieser Artikel diskutiert den Charakter von Pollentypen. Wir argumentieren, dass Pollentypen und Pflanzentaxa komplett unterschiedliche Entitäten (morphologische bzw. taxonomische) sind, und deswegen unterschiedlich behandelt und dargestellt werden sollten. Allgemeine Probleme der konventionellen Nomenklatur von Pollentypen werden anhand von Beispielen aus der europäischen palynologischen Praxis illustriert. Wir plädieren für Deutlichkeit in der Nomenklatur von Pollentypen und für die wissenschaftliche Freiheit, ‘unkonventionelle‘ Methoden zu benutzen, um Verwirrung zu vermeiden.

Description: research

Description: Remarkable technological advances have revealed ever more properties and behaviours of individual microorganisms, but the novel data generated by these techniques have not yet been fully exploited. In this Opinion article, we explain how individual-based models (IBMs) can be constructed based on the findings of such techniques and how they help to explore competitive and cooperative microbial interactions. Furthermore, we describe how IBMs have provided insights into self-organized spatial patterns from biofilms to the oceans of the world, phage–CRISPR dynamics and other emergent phenomena. Finally, we discuss how combining individual-based observations with IBMs can advance our understanding at both the individual and population levels, leading to the new approach of microbial individual-based ecology (μIBE).

Description: Ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) is a key enzyme of the Calvin cycle, which is responsible for most of Earth's primary production. Although research on RubisCO genes and enzymes in plants, cyanobacteria and bacteria has been ongoing for years, still little is understood about its regulation and activation in bacteria. Even more so, hardly any information exists about the function of metagenomic RubisCOs and the role of the enzymes encoded on the flanking DNA owing to the lack of available function-based screens for seeking active RubisCOs from the environment. Here we present the first solely activity-based approach for identifying RubisCO active fosmid clones from a metagenomic library. We constructed a metagenomic library from hydrothermal vent fluids and screened 1056 fosmid clones. Twelve clones exhibited RubisCO activity and the metagenomic fragments resembled genes from Thiomicrospira crunogena. One of these clones was further analyzed. It contained a 35.2 kb metagenomic insert carrying the RubisCO gene cluster and flanking DNA regions. Knockouts of twelve genes and two intergenic regions on this metagenomic fragment demonstrated that the RubisCO activity was significantly impaired and was attributed to deletions in genes encoding putative transcriptional regulators and those believed to be vital for RubisCO activation. Our new technique revealed a novel link between a poorly characterized gene and RubisCO activity. This screen opens the door to directly investigating RubisCO genes and respective enzymes from environmental samples.

Description: Ocean acidification, the drop in seawater pH associated with the ongoing enrichment of marine waters with carbon dioxide from fossil fuel burning, may seriously impair marine calcifying organisms. Our present understanding of the sensitivity of marine life to ocean acidification is based primarily on short-term experiments, in which organisms are exposed to increased concentrations of CO2. However, phytoplankton species with short generation times, in particular, may be able to respond to environmental alterations through adaptive evolution. Here, we examine the ability of the world’s single most important calcifying organism, the coccolithophore Emiliania huxleyi, to evolve in response to ocean acidification in two 500-generation selection experiments. Specifically, we exposed E. huxleyi populations founded by single or multiple clones to increased concentrations of CO2. Around 500 asexual generations later we assessed their fitness. Compared with populations kept at ambient CO2 partial pressure, those selected at increased partial pressure exhibited higher growth rates, in both the single- and multiclone experiment, when tested under ocean acidification conditions. Calcification was partly restored: rates were lower under increased CO2 conditions in all cultures, but were up to 50% higher in adapted compared with non-adapted cultures. We suggest that contemporary evolution could help to maintain the functionality of microbial processes at the base of marine food webs in the face of global change.

Description: Climate variability in the tropical Atlantic Ocean is determined by large-scale ocean–atmosphere interactions, which particularly affect deep atmospheric convection over the ocean and surrounding continents1. Apart from influences from the Pacific El Niño/Southern Oscillation2 and the North Atlantic Oscillation3, the tropical Atlantic variability is thought to be dominated by two distinct ocean–atmosphere coupled modes of variability that are characterized by meridional4, 5 and zonal6, 7 sea-surface-temperature gradients and are mainly active on decadal and interannual timescales, respectively8, 9. Here we report evidence that the intrinsic ocean dynamics of the deep equatorial Atlantic can also affect sea surface temperature, wind and rainfall in the tropical Atlantic region and constitutes a 4.5-yr climate cycle. Specifically, vertically alternating deep zonal jets of short vertical wavelength with a period of about 4.5 yr and amplitudes of more than 10 cm s−1 are observed, in the deep Atlantic, to propagate their energy upwards, towards the surface10, 11. They are linked, at the sea surface, to equatorial zonal current anomalies and eastern Atlantic temperature anomalies that have amplitudes of about 6 cm s−1 and 0.4 °C, respectively, and are associated with distinct wind and rainfall patterns. Although deep jets are also observed in the Pacific12 and Indian13 oceans, only the Atlantic deep jets seem to oscillate on interannual timescales. Our knowledge of the persistence and regularity of these jets is limited by the availability of high-quality data. Despite this caveat, the oscillatory behaviour can still be used to improve predictions of sea surface temperature in the tropical Atlantic. Deep-jet generation and upward energy transmission through the Equatorial Undercurrent warrant further theoretical study.

Description: The dehydration of subducting oceanic crust and upper mantle has been inferred both to promote the partial melting leading to arc magmatism and to induce intraslab intermediate-depth earthquakes, at depths of 50–300 km. Yet there is still no consensus about how slab hydration occurs or where and how much chemically bound water is stored within the crust and mantle of the incoming plate. Here we document that bending-related faulting of the incoming plate at the Middle America trench creates a pervasive tectonic fabric that cuts across the crust, penetrating deep into the mantle. Faulting is active across the entire ocean trench slope, promoting hydration of the cold crust and upper mantle surrounding these deep active faults. The along-strike length and depth of penetration of these faults are also similar to the dimensions of the rupture area of intermediate-depth earthquakes.

Description: Nitrous oxide is a potent greenhouse gas and a key compound in stratospheric ozone depletion. In the ocean, nitrous oxide is produced at intermediate depths through nitrification and denitrification, in particular at low oxygen concentrations. Although a third of natural emissions of nitrous oxide to the atmosphere originate from the ocean, considerable uncertainties in the distribution and magnitude of the emissions still exist. Here we present high-resolution surface measurements and vertical profiles of nitrous oxide that include the highest reported nitrous oxide concentrations in marine surface waters, suggesting that there is a hotspot of nitrous oxide emissions in high-productivity upwelling ecosystems along the Peruvian coast. We estimate that off Peru, the extremely high nitrous oxide supersaturations we observed drive a massive efflux of 0.2–0.9 Tg of nitrogen emitted as nitrous oxide per year, equivalent to 5–22% of previous estimates of global marine nitrous oxide emissions. Nutrient and gene abundance data suggest that coupled nitrification–denitrification in the upper oxygen minimum zone and transport of resulting nitrous oxide to the surface by upwelling lead to the high nitrous oxide concentrations. Our estimate of nitrous oxide emissions from the Peruvian coast surpasses values from similar, highly productive areas.

Description: Cultivated bacteria such as actinomycetes are a highly useful source of biomedically important natural products. However, such ‘talented’ producers represent only a minute fraction of the entire, mostly uncultivated, prokaryotic diversity. The uncultured majority is generally perceived as a large, untapped resource of new drug candidates, but so far it is unknown whether taxa containing talented bacteria indeed exist. Here we report the single-cell- and metagenomics-based discovery of such producers. Two phylotypes of the candidate genus ‘Entotheonella’ with genomes of greater than 9 megabases and multiple, distinct biosynthetic gene clusters co-inhabit the chemically and microbially rich marine sponge Theonella swinhoei. Almost all bioactive polyketides and peptides known from this animal were attributed to a single phylotype. ‘Entotheonella’ spp. are widely distributed in sponges and belong to an environmental taxon proposed here as candidate phylum ‘Tectomicrobia’. The pronounced bioactivities and chemical uniqueness of ‘Entotheonella’ compounds provide significant opportunities for ecological studies and drug discovery.

Description: During the past decades climate and freshwater dynamics in the northwestern North Atlantic have undergone major changes. Large-scale freshening episodes, related to polar freshwater pulses, have had a strong influence on ocean variability in this climatically important region. However, little is known about variability before 1950, mainly due to the lack of long-term high-resolution marine proxy archives. Here we present the first multidecadal-length records of annually resolved Ba/Ca variations from Northwest Atlantic coralline algae. We observe positive relationships between algal Ba/Ca ratios from two Newfoundland sites and salinity observations back to 1950. Both records capture episodical multi-year freshening events during the 20th century. Variability in algal Ba/Ca is sensitive to freshwater-induced changes in upper ocean stratification, which affect the transport of cold, Ba-enriched deep waters onto the shelf (highly stratified equals less Ba/Ca). Algal Ba/Ca ratios therefore may serve as a new resource for reconstructing past surface ocean freshwater changes.

Description: Palaeoclimate records and numerical model simulations indicate that changes in tropical and subtropical sea surface temperatures and in the annual average position of the intertropical convergence zone are linked to high-latitude climate changes on millennial to glacial–interglacial timescales. It has recently been suggested that cooling in the high latitudes associated with abrupt climate-change events is evident primarily during the northern hemisphere winter, implying increased seasonality at these times8. However, it is unclear whether such a seasonal bias also exists for the low latitudes. Here we analyse the Mg/Ca ratios of surface-dwelling foraminifera to reconstruct sea surface temperatures in the northeastern Gulf of Mexico for the past 300,000 years. We suggest that sea surface temperatures are controlled by the migration of the northern boundary of the Atlantic Warm Pool, and hence the position of the intertropical convergence zone during boreal summer, and are relatively insensitive to winter conditions. Our results suggest that summer Atlantic Warm Pool expansion is primarily affected by glacial–interglacial variability and low-latitude summer insolation. Because a clear signature of rapid climate-change events, such as the Younger Dryas cold event, is lacking in our record, we conclude that high-latitude events seem to influence only the winter Caribbean climate conditions, consistent with the hypothesis of extreme northern-hemisphere seasonality during abrupt cooling events.

Description: Infections arising from multidrug-resistant pathogenic bacteria are spreading rapidly throughout the world and threaten to become untreatable. The origins of resistance are numerous and complex, but one underlying factor is the capacity of bacteria to rapidly export drugs through the intrinsic activity of efflux pumps. In this Review, we describe recent advances that have increased our understanding of the structures and molecular mechanisms of multidrug efflux pumps in bacteria. Clinical and laboratory data indicate that efflux pumps function not only in the drug extrusion process but also in virulence and the adaptive responses that contribute to antimicrobial resistance during infection. The emerging picture of the structure, function and regulation of efflux pumps suggests opportunities for countering their activities.

Description: Plant species diversity regulates the productivity1–3 and stability2,4 of natural ecosystems, along with their resilience to disturbance5,6. The influence of species diversity on the productivity of agronomic systems is less clear7–10. Plant genetic diversity is also suspected to influence ecosystem function3,11–14, although empirical evidence is scarce. Given the large range of genotypes that can be generated per species through artificial selection, genetic diversity is a potentially important leverage of productivity in cultivated systems. Here we assess the effect of species and genetic diversity on the production and sustainable supply of livestock fodder in sown grasslands, comprising single and multispecies assemblages characterized by different levels of genetic diversity, exposed to drought and non-drought conditions. Multispecies assemblages proved more productive than monocultures when subject to drought, regardless of the number of genotypes per species present. Conversely, the temporal stability of production increased only with the number of genotypes present under both drought and non-drought conditions, and was unaffected by the number of species. We conclude that taxonomic and genetic diversity can play complementary roles when it comes to optimizing livestock fodder production in managed grasslands, and suggest that both levels of diversity should be considered in plant breeding programmes designed to boost the productivity and resilience of managed grasslands in the face of increasing environmental hazards.

Description: 33 species of polychaetes were collected, 27 of them were determined to species level. The majority of the species are cosmopolitans. Pulliella armata FAUVEL was found the first time in the Atlantic Ocean off Northwest Africa.

Description: The new Harpacticoidea genus Thieliella nov. gen. of the family Ancorabolidae SARS sensu LANG, 1909 with two new species from 500 m depth of the Island-Faroer-Ridge is described and discussed: Thieliella nordatlantica nov. spec. and Th. reducta nov. spec.

Description: 80 species of polychaetes were collected, 76 of them were determined to species level. One species (Harmothoe [Austrolaenilla] meteorae n. sp.) was described as new species. The majority of the species including the species of the cruises 26 and 44 are cosmopolitans (18%); 16% are distributed in cool temperate to tropical zones, 12.5% have their distribution in the eastern Atlantic and the Mediterranean, and 11% are distributed in tropical-subtropical to warm temperate zones.

Description: Nine species of Flustridae were collected by the R.V. "Meteor" in one subantarctic and three antarctic stations. Two new genera (Austroflustra and Neoflustra) and three new species (Austroflustra gerlachi, A. australis and Neoflustra dimorphica) are described. The diagnosis of the family is emended to include species with adventitious avicularia. Nematoflustra bifoliata D'HONDT and Flustra thysanica MOYANO are placed in the genus Securiflustra SILEN, and Flustra vulgaris KLUGE is transfered to Austroflustra.

Description: The species Stenhelia (Delavalia) noodti n. sp., Stenhelia (Delavalia) islandica n. sp., Pseudomesochra scheibeli n. sp. and Ameira faroerensis n. sp. are described from 500 m depth on the Island-Faroer-Ridge. Of special interest is Stenhelia (Delavalia) noodti n. sp. showing a reduction of the Exp A2 to one segment, a character described for this genus for the first time.

Description: In samples from the Iberian Basin and off Cape Blanc, dredged from below 2000 m, 10 species of ophiuroids were found, viz. Ophioscolex sp., Ophiambix meteoris, Amphioplus verrilli, Amphilepis sp., Ophiochiton ternispinus, Amphiophiura convexa, Ophiocten latens, Ophiura ljungmani, Ophiomusium lymani, and Ophiosphalma armigerum. The distribution of the species found is summarized. The descriptions of Amphioplus verrilli, Ophiochiton ternispinus, Ophiomusium lymani, and Ophiosphalma armigerum are extended. Silax pulvinus is supposed to be synonymous with Amphioplus verrilli. The genus Silax is withdrawn. Most of the genera and many of the species are cosrnopolitans. The ophiuroids found have no morphological characteristics distinguishing them as deep-sea forms.

Description: A general study of structure, biomass, and dynamic estimates on meiofauna was carried out during PREFLEX (1975) and FLEX (1976), in 117-141 m water depth. On the basis of these data an attempt was made to estimate meiofauna production, and this is discussed in relation to the energy input from the spring phytoplankton bloom. Sampling was performed at five stations, but only the stations 1, 4, and 5 were covered by a complete series from August 1975 to July 1976. At each station, from four replicate box core samples, two were withdrawn to study the abundance, distribution, and biomass of meiofauna, the content of chloroplastic pigment equivalents (CPE), and chemical and grain size analyses. At all stations grain size feil in the range of fine sand having median diameters (MD) of 〈125 μm. From Station 1 to 5 an increase in MD was observed. Highest values of CPE (7.81 μg ml-1) and organic matter (4.7%) were obtained in June and July (1976)/August (1975), respectively. Meiofauna abundance was fairly uniform at all stations examined. Station 1 displayed maximal numbers during the whole investigation period. The abundance per 100 cm2 varied between 15,550 and 34,900 organisms. All meiofauna studied both in total and as separate taxa showed annual cycles of abundance. Low abundance values were recorded during early summer, and maximum values during winter. High numbers of Foraminifera were obtained for August 1975 (9,460 per 100 cm2) and July 1976 (9,710 per 100 cm2). From December to June the values decreased from 3,280 to 1,030 per 100 cm2. At station 1 maximum values of meiofauna biomass were recorded ranging from 1.5 to 2.7 g DWT m-2. The mean meiofauna dry weight amounted to 2.1 g DWT m-2. Based on minimum production, the P/B ratio for the area of Station 1 might have a mean of 1.4. Taking into consideration generation times we believe that a turnover ratio of 2 is a conservative value for the Fladen Ground meiofauna. The annual production would amount to 4.2 g DWT m-2 yr-1. This is 27.5% of the energy supply during the spring phytoplankton bloom, which is channelled into the meiofauna. The hypothesis is put forward that the energetic strategy of deep offshore meiofauna differs distinctively from that of shallow inshore meiofauna. While the shallow inshore meiofauna show a relatively fast response to organic matter input, the deep offshore meiofauna reacts much more slowly, the food energy consumption seems to be spread out over a longer period.

Description: A general study of structure, biomass estimates and dynamics on the macrofauna was carried out in August 1975 and March 1976 during PREFLEX (1975) and FLEX (1976), the Fladen Ground Experiment. On the basis of these data an attempt was made to estimate macrobenthic production expressed as minimum production (MP). The macrobenthic production is discussed together with meiobenthic annual production (FAUBEL, HARTWIG & THIEL 1983) and with indirectly estimated microbenthic production in relation to an energy input from the water column of about 25g C m-2 year-1 (STEELE 1974). From the production estimates of the three benthic components a rough energy budget is proposed. Sampling was performed at five Stations for endofauna twice during the time of investigation and for epifauna once. At each station two replicate box core samples (30 X 20 cm) were taken for endofauna. Epifauna was sampled with an Agassiz trawl once at each Station. The total numbers of endofauna increased from station l to 5. This was valid as well for August 1975 (4,233-12,166 individuals per m2 and 10 cm sediment depth) as for March 1976 (1,008-2,925 individuals). The polychaetes were the dominant organisms with a share of 33 to 62%. The densities for the endofauna decreased from August 1975 to March 1976 by a mean factor of 2.8. Abundances of epifauna amounted to values between 11 and 102 individuals per 1000 m2. The biomass dry weights (DWT) for macrobenthic endofauna varied between 0.97g DWT m-2 and 6.42g DWT m-2 in August 1975 and between 0.27g DWT m-2 and 2.64g DWT m-2 in March 1976. The mean amounted to 1.74g DWT m-2. Dry weights of epifauna biomass gave values between 4.9 and 83.1g DWT, 1000 m-2. The minimum production for the total macro-endofauna at Fladen Ground amounted to 1.43g DWT m-2 yr-1 or 0.82g C m-2 yr-1. This resulted in a minimum turnover rate (P/B) of 0.8. The share produced by the polychaetes amounted to 1.06g DWT m-2 yr-1 or 74%.

Description: Based on more than 1800 neuston tows, the ranges and mean abundances per area of 10 taxa of beloniform fish are calculated. The distributional patterns of fry of most oceanic taxa are a consequence of both surface temperatures and direction of currents. Oxyporhamphus microptems has a strictly tropical distribution; in the centre of its distribution the mean abundance reaches 10-50 ind./1000 m2. Nanichthys simulans occurs polewards of 0. micropterus, mainly within the great warm circulation systems. Scomberesox saurus has a bipolar subtropical-temperate distribution with seasonal shift of the boundaries, and a general abundance of 30-40 ind./1000 m2, though in subtropical frontal zones values above 100 ind./1000 m2 are common. Exocoetus volitans covers the warmer parts of the Atlantic, but has two antiequatorial belts of maximum abundance within the tropics (25-35 ind./1000 m2). The other exocoetid taxa have similar poleward boundaries as E. volitans. E. obtusirostris and genus Cypselurus average 1.5 ind./1000 m2, whilst Prognichthys gibbifrons, Danichthys rondeletii and genus Hirundichthys have mean abundances of an order of 0.5 ind./1000 m2. Belone svetovidovi is strictly neritic, and shows great regional differences of abundance off NW Africa.

Description: Macro- and meiobenthic abundance and biomass as well as metabolic activity (respiration, ETS activity) have been studied along a transect ranging from 130 to 3000 m water depth off northern Morocco (35° N) during "Meteor" cruise No. 53 (1980). The distribution of chloroplastic pigment concentration (chlorophyll a, pheophytins) in the sediment has been investigated as a measure of sedimented primary organic matter. High chloroplastic pigment concentrations were found on the shelf and around the shelf break, but values declined rapidly between 200 and 600 m depth. Below 1200 m pigment concentrations remained at a relatively uniform low level. Macrobenthic abundance and biomass (wet weight) decreased with increasing water depth and with distance from the shore. Significant changes occurred between the shelf and upper slope and below 2000 m depth. Meiobenthic abundance and biomass (ash free dry weight) followed the same general pattern, but changes were found below 400 and 800 m depth. In the depth range of 1200 to 3000 m values differ only slightly. Meiofauna abundance and biomass show a good correlation with the sedimentary chloroplastic pigment concentrations. Respiratory activity of sediment cores, measured by a shipboard technique at ambient temperatures, decreased with water depth and shows a good correlation with the pigment concentrations. ETS activity was highest on the shelf and decreased with water depth, with significant changes between 200 and 400 m, and below 1200 m depth, respectively. Activity was generally highest in the top 5 cm of the sediment and was measurable, at all Stations, down to 15 cm sediment depth. Shelf and upper slope stations exhibited a vertical distribution pattern of ETS activity in the sediment column, different from that of deeper Stations. The importance of biological activity measurements as an estimate of productivity is discussed. To prove the thesis that differences in benthic abundance, biomass and activity reflect differences in pelagic surface primary production, in the case of the NW-African coast caused by different upwelling intensities, the values from 35° N were compared with data from 21° N (permanent upwelling activity) and 17° N (ca. 9 months upwelling per year). On the shelf and upper slope (〈 500 m) hydrographical conditions (currents, internal waves) influence the deposition of organic matter and cause a biomass minimum between 200 and 400 m depth in some regions. But, in general, macrobenthic abundance and biomass increases with enhanced upwelling activity and reaches a maximum in the area off Cape Blanc (21° N). On the shelf and in the shelf break region meiofauna densities are higher at 35° N in comparison to 21° N; but in contrast to the decreasing meiofauna abundance with increasing water depth at 35° N, an abundance maximum between 400 and 1200 m depth is formed in the Cape Blanc region; this maximum coincides with the maximum of sedimenta1y chloroplastic pigment equivalents. The comparison of ETS activities between 35° N and 21° N shows on the shelf activity at 21° N is up to 14 times higher and on the slope 4-9 times higher, which demonstrates that benthic activity responds to the surface productivity regime.

Description: 7 new Harpacticoidea species and the female of a known species of the family Cletodidae (Crustacea, Copepoda) new to science are dealt with in this paper. Heteropsyllus serratus n. sp. Mesocletodes trisetosa n. sp. Mesocletodes parabodini n. sp. Mesocletodes variabilis n. sp. Paranannop11s plumosus n. sp. Paranannopus langi WELLS, 1965 ♀ Metahuntemannia pseudomagniceps n. sp. Metahuntemannia atlantica n. sp. As far as possible the species relationships within each genus are discussed. All species were collected at 500 m depth on the Iceland-Faroer-Ridge.

Description: In the present paper results of taxonomic investigations on 1137 specimens of Cyllopus magellanicus DANA 1853 and of 730 specimens of Cyllopus lucasii BATE 1862 are reported. A brief diagnosis and key are given for the genus and the species. For the first time larvae of the pantochelis stage of these species are described. The habitus of the larvae are very similar, small differences were found on the structures of the pereopod 3-6. Due to special morphological similarities it is concluded that the larvae of both species display a parasitic way of life like Vibilia. The distribution of the species in the Antarctic Ocean is circumpolar: C. magellanicus occurs probably only within the West Wind Drift while C. lucasii was found within both the West and the East Wind Drift. Remarkable is the occurrence of a great number of males of C. magellanicus in the uppermost layer (30-0 cm depth), meanwhile the females of this species were found only in deeper layers.

Description: Light and electron microscopic examination of a number of dpecies previously attributed to the genus Syracosphaera LOHMANN show that three groups can be delimited, all of which warrant generic status. Caneosphaera GAARDER and Coronosphaera GAARDER are described, and the genus Syracosphaera with type species the two-layered S. pulchra LOHMANN is emended with redescription in terms of morphological features seen under light and electron microscope. New combinations are presented for five species.

Description: 1. 52 species of Crustacea Decapoda Reptantia, one of which new, were obtained on the cruises of R. V. "Meteor" dealt with in this paper. 2. The status of Euchirograpsus liguricus and E. americanus is discussed in some detail. It is shown that E. americanus is restricted to the western Atlantic, while E. liguricus occurs only in the eastern Atlantic. Records of E. americanus outside the western Atlantic are due to confusions with E. liguricus or other new species which have been described elsewhere (TÜRKAY 1975). 3. 3 species ( Polycheles crucifera, Munida iris ruttlandi, Cymonomus normani) are recorded for the first time from the Portuguese and 4 species ( Polycheles granulatus, Munida iris ruttlandi, Jaxea nocturna1, Macropipus rugosus) from the Moroccan coast. 4. The characterization of the Moroccan and Lusitanic province may be performed quantitatively rather than qualitatively. Further investigations are needed in order to get complete results.

Description: This paper deals with Euphausiacea collected in the upwelling region off Northwest Africa between Cap Blanc and Cap Mirik (Timiris) during the voyages 19 (1970) and 26 (1972) of the research vessel "Meteor". 20 species have been recorded, 4 of these dominate in the area under study. Euphttsia krohnii, Nematoscelis megalops and Thysanoessa gregaria are atlantic temperate species, whereas Nyctiphanes capensis inhabits neritic areas around the edge of the Banc d' Arguin, together with Euphausia hanseni from the Southern Atlantic. The population density of the euphausiids in the upwelling area is very high. The vertical distribution of the dominant species E. krohnii and N. megalops reveal significant differences. E. krohnii occurs down to a depth of 200 m, whereas N. megalops lives between 100 and 300 m. The shelf and the edge of the shelf (down to 2000 m) are populated by different species. On the shelf, adult and juvenile N. capensis predominate, but great numbers of juvenile N. megalops have also been found. Along the edge of the shelf E. krohnii, N. megalops and T. gregaria are most abundant. E. hanseni was represented by juveniles, both on the shelf and along its edge. Comparing the species composition of the area under study with that of other regions of the North Atlantic, the dominant species exhibit certain similarities with the species present near Cap Verde and Canary Island, but none similarities could be established with the Great Meteor Seamount. The reasons for this situation are discussed.

Description: Through correspondence, the authors determined that each possessed material of an undescribed wrasse of the genus Suezichthys SMITH. The first five specimens of this species were taken in December, 1964 by R. V. "Anton Bruun" while trawling in 78-82 m and in 70-80 m (2 and 3 specimens resp.) off the Somali Republic, East Africa; the next two were collected a month later by R. V. "Meteor" by trawl off Kenya in 124-130 m; the last two were trawled in July and October, 1972 by U. S. National Marine Fisheries Service research vessel "Townsend Cromwell" off Oahu, Hawaiian Islands in 119-168 m. These nine specimens form the basis for the description herein of this new labrid fish.

Description: 46 hydropolyp species of 28 genera and 10 families were sampled during the "Meteor" passage 1964/65 (IIOE) through the Red Sea and its northern and southern exits and on the occasion of several ecological investigations of 29 selected coral reef sections of the central Red Sea and the Gulf of Aqaba. These collections comprise 128 single records of hydropolyp species. Three species and two genera each with one species are doubtful. 25 species, seven genera, one family and one subfamily, together from 49 records have not previously been found in the Red Sea and its exits. Including these newly reported species, the total list increases from 64 species and 112 records (SCHMIDT 1972) to 89 species and 240 single records and 51 additional ones. Scanning microscopical photos, made for the first time for the illustration of the hydropolyps, have been shown to be suitable for a better characterization and diagnosis of the species. Qualified results on the reasons for the horizontal distribution of the species known from the Red Sea area cannot be given because of the low number of samples sporadically distributed through the whole area. In contrast with this fact, the vertical spread of the species sampled seems primarily to be regulated by water exchange and light intensity. For example, four species of hydropolyps are excellent indicators of certain abiotic factors or combinations of them: Gymnangium eximium reacts extremely stenophote-photophobe-rheophil, Eudendrium ramosum moderately stenophote-photophobe-rheophobe, Lytocmpus philippinus moderately stenophotephotophil-rheophil, and Halocordyle disticha var. australis extremely stenophote-photophil but moderately rheophil. Other species have been found throughout all the light zones. Combined with the small size of their colonies their euryphotic behaviour does not allow their use as indicator species.

Description: Four species of gammaridean Amphipoda are recorded from the Iberian deep sea basin at about 5000 m depth: Bathyceradocus iberiensis sp. n., Paracallisoma platepistomum sp. n., Parandaniexis cf. mirabilis SCHRELLENBERG, 1929, and Parargissa galatheae BARNARD, 1961. The biogeography of the four species is discussed.

Description: Using a Bongo-Net equipped with a multiple codend closing device, the vertical distribution of siphonophores has been observed in 100 m depth intervals at 13 stations off Cap Mirik (19° N) (from 0-500 m depth). The distributional pattern of the 15 siphonophores species found is discussed in relationship to the hydrography of this upwelling region. The following main features have been observed in comparison with the warmer oceanic water offshore: (1) a lower diversity, (2) a shallower distribution of some of the deep living species due to the lower temperature in the upper 300 m and a lower transparency, (3) no contribution to acoustic scattering by physonect siphonophores.

Description: From sublittoral silty sediments (118 m depth) of the North Sea (59° 0.5' N; 01° 20.5' E), Bathymacrostomum spirale n. gen. n. sp. is described on the basis of squeeze preparation. According to the organization of the cuticular apparatus of the bursal organ the species belongs to the family Dolichomacrostomidae RIEGER, 1971. The absence of an accessory gland organ and the simplicity of the penis stilet leads to the establishment of the subfamily Bathymacrostominae nov. subfam.

Description: Description of Acanthophmyngoides quintus nov. spec. (Desmodorinae) with discussion of the systematical relationship to Spiriniinae and Pseudonchinae, and description of Richtersia iberica nov. spec. with discussion of the relationship to Desmodorinae.

Description: The Great Meteor Seamount is situated in the subtropical NE Atlantic. The dimension of the plateau in the depth of 400m is 1465 km2 ; its lowest depth 275 m. 35 species have been caught above the plateau in 1967 and 1970 (voyages 9 c and 19; R. V. "Meteor") with a bottom trawl, the Agassiz-trawl, with BEYER's epibenthic closing net, the triangle-dredge and the chain-dredge. For comparison fishes of the same species were collected off Morocco, Mauretania and Senegal. The circular current system above the seamount and the low rates of the net transport are the reasons for the existence of the autochthonous demersal fish populations, in spite of the pelagic stages of development. A comparison of the populations of three species from the seamount and from the African shelf, using a multivariate method (linear discriminant function), indicates a genetical diverging development of the populations. An overlapping of the populations is only applicable for 1.7 % of the individuals. This argument for an autochthonus demersal fish fauna is corroborated by nearly the same composition of species in 1967 and 1970, the small differences in the dominance of the species and the great homogeneity of the fish fauna in the two years. The distribution of the species above the plateau is nearly uniform. The species Aulopus filamentosus, Phycis phycis, Macroramphosus scolopax, Anthias anthias, Antigonia capros, Capros aper, Callionymus phaeton and Arnoglossus rueppelli are characteristic for the fauna, as in 6 of 11 comparable catches these 8 species were present together. For the demersal fishes the plateau is a rather uniform biotope, for it is mainly covered with biogenic sand. The aggregations of the seamount's own plankton and nekton near the bottom in daytime is exclusively or partly the food for 94% of the fish species, while the bottom fauna is only utilized by 22% of the species. Only Callionymus phaeton feeds exclusively on bottom animals. Shrimps (predominantly Plesionika heterocarpus) are the favoured prey of the majority of fish species. Relative to the number of examined stomachs the small crustacea like ostracodes and copepods are most abundant. Fishes were found in the stomachs of 8 species. Moreover cuttle-fish are of some importance as food of the bigger fishes. A comparison of the food of respective species from the African shelf shows that the lower availability of food above the seamount has no influence on the feeding behaviour of the species. lt seems, that there is sufficient food at the seamount, so that the fishes must not put up with animals they disdain elsewhere. The fish fauna from the Great Meteor Seamount shows the greatest similarity with the demersal fish fauna of the African shelf between Gibraltar and Cap Blanc (28 species in common). The Great Meteor Seamount has only 24 species in common with Madeira and 17 with the Canary Islands. Two species suggest a possible influence of settlement from the Western Atlantic. These species also belong to the fauna of Madeira and the Josephine Seamount, while they are absent on the African shelf. The species Gnathophis codoniphorus, Callionymus sousai and probably also the ray of the genus Raja are endemic. The depth of the plateau (275-400 m) has a great influence on the composition of the fish fauna. Regarding the vertical distribution of the species in the rest of their distribution areas, the plateau of the Great Meteor Seamount is situated at the optimal depth.

Description: 85 species of polychaetes were collected, 72 of them were determined to species level. One genus (Palposyllis n. g.), four species (Pionosyllis gorringensis n. sp., Palposyllis prosostoma n. sp., Potamethus filiformis n. sp., Potamethus breviuncatus n. sp.), and one subspecies (Ophelina delapidans longicephala n. subsp.) were described as new taxa. The majority of the species collected during this cruise have their distribution in the Atlantic Ocean or are more widely distributed. Peisidice bermudensis was found the second time after its original description. Lepidastenia brunnea and Isolda whydahensis never have been found as far north off the coast of Portugal. The interstitial living species Pisione remota and Hesionides arenaria, usually common in shallow waters, were found in deeper water (72 m and 120-180 m) for the first time.

Description: Off the NW-African coast in February 1973 neuston was sampled between latitudes 36° and 30° N as part of the CINECA multiship survey. The ichthyoplankton, fish larvae only, of these neuston samples was investigated under qualitative and quantitative aspects. Due to winterly environmental conditions and a more northern station-grid compared to the other "Meteor" expeditions, the total yield was low, for subtropical faunistic elements were absent or less abundant. The northern neritic part showed densities of only 3.0 fishes/100 m3 of water filtered, in the southern neritic zone maximum values occurred with 18.9 animals/100 m3, but even these values were far lower than those found in winter 1970, when surfacetemperatures and the amount of subtropical species were higher. The investigated area is considered to be a transitional zone between boreal and subtropical conditions under regional and seasonal aspects. For the most frequent taxa earlier findings on zoogeography, behaviour and ecology could be confirmed and completed.

Description: The report considers all planktonic stages of the Mysidacea Lophogastrida, Amphionidacea and Decapoda taken by R.V. "Meteor" in plankton samples over Josephine and Great Meteor Seamounts and regions of similar latitude off the Portuguese and Moroccan coasts. Larvae of most species in the vicinity of the seamounts were virtually confined to the upper 100 m. Circadian vertical migration was not evident. The waters over the seamounts were not avoided by holopelagic species. Such waters yielded fewer species of meroplanktonic larvae than the coastal regions and showed few species in common with each other or with the coastal regions. One larval species from both seamounts and three from Great Meteor Seamount show major characters unknown in larvae from European or North African waters.

Description: Taxonomical study of the Bryozoa collected during the cruises of R. V. "Meteor" near the French coast (Atlantic and Channel) and the coastline of Mauritania. First indications of Arachnoidea annosciae n'HONDT and GERACI, 1976, Onychocella antiqua (BUSK, 1858) and Cribrilaria flabellifera (KIRKPATRICK, 1888) in the temperate region of the North Atlantic.

Description: A study of recent publications on ichthyoneuston of subtropical seas showed that this fauna is neither regionally nor seasonally uniform. Available material of abundant and characteristic species off Northwest Africa was re-examined under this aspect. This material was collected during five German expeditions (1967-1973) between 20° and 36° N and between the coast and 30° W. It includes 366 hauls that could be utilized for qualitative analysis; out of these 333 hauls yielded quantitative information. Based upon variation in geographical and hydrographical factors, distribution of sampling locations and zoogeographical considerations, the study area was divided into five subregions (two neritic and three oceanic), each represented by a different number of samples. A clear faunistic boundary appears between neritic and oceanic subregions. This boundary is related to water depth and distance from shore. It is sharp for neritic species. It is also sharp for mesopelagic fishes as they do not occur in water shallower than the slope, whereas oceanic-epipelagic taxa are less affected by this boundary. Latitudinal zonation is also evident as it is a function of hydrographic factors, especially temperature, probably showing seasonal variations. The latitudinal boundary is less pronounced than the neriticoceanic one; simplified it is assumed as running through the Canary Islands region. In all subregions, ichthyoneuston abundances appear to be highest during winter months. Maximum of abundance is produced by spawning that is restricted in many species to this season. The five most common species constituted more than 80% of the total catch during winter. Their proportion decreased to less than 60% in warmer months due to the immigration of less common (largely tropical) species and the mortality and ontogenetic emigration of animals born during winter. Seasonal differences in diversity did not prove significant as species number in ichthyoneuston catches is generally high. Seasonal trends are conspicuous for typical species only and are discussed. The northwest African current system probably causes considerable drift in ichthyoplankton. This raises the question as to how stocks survive despite drift of early life stages. This problem is discussed for characteristic taxa. Depending on the species, several mechanisms acting either singly or in combination are possible: 1. Adults of tropical neustonic forms actively migrate into the study area in summer, passive southward transport of early stages being a necessary condition for survival during other seasons. 2. Southward transport of species performing diurnal vertical migrations may, in certain areas, be reduced if such species reach the poleward undercurrent and remain in it during part of the day. 3. South of Cape Blanc, inshore eddies and the temporary surface countercurrent may permit a longer stay or return transport. This mechanism is probably effective for neritic euneustonic animals.

Description: This paper deals with the presence and distribution of Thecosomatous Pteropods in the Indian Ocean. 122 plankton-samples, taken by R.V. "Meteor" during the International Indian Ocean Expedition (IIOE) in 1964-65 were investigated. They contain a total number of about 45000 Thecosomata, belonging to 22 species and 5 families. Some species (e.g. Creseis acicula and Limacina inflata) are common in the entire area, others (e.g. Creseis chierchiae and Desmopterus gardinieri) show a quite distinct distribution. From several species only one single specimen was captured, others are completely lacking in the collection though they have been reported frequently from the same area by other expeditions. This may be due to seasonal variations and to the fact that to bathial tows were taken. In spite of these restrictions the extensive material from a relatively small area offers the possibility to compare specific and nonspecific features in related species and to question their taxonomic value.

Description: In samples from the Indian and the Atlantic Ocean the size distribution of detritus particles was estimated by collecting the particles on membrane filters, drying, photographing and subsequent counting them by means of a Zeiss particle size analyzer. Parallel countings were made after the settling down of the particles at the bottom of sedimentation chambers and photographing them in an inverted plankton microscope. The size distribution of detritus particles is given in terms of concentration of detritus, either as number of particlcs per litre, or volume of detritus per litre. As was already observed by BRUN-COTTAN & IVANOFF (1971), in the mean of a series of different samples, the size distribution of detritus particles, in terms of concentration by number follows a decreasing logarithmic function; whereas the same, in terms of concentration by volume probably follows an increasing logarithmic function. In terms of linear presentation this would be a hyperbola and a parabola, respectively. By the plankton microscope method much more particles were obtained than by the membrane filter method. By the latter only solid particles were counted, whereas soft particles, that in nature are bloated by their inner water, disappear. Samples of different origin differ by the absolute number of particles and the gradient of the regression. Thus, the particle size analysis may serve as a means for characterization of water bodies.

Description: 85 subsamples with coelenterates collected during the "Meteor"-Expedition into the Arabian Sea and sorted out in Kiel were checked for hydromedusae. Furthermore ten samples from the southern entrance of the Red Sea and 29 samples from the "John-Murray"-Expedition into the Indian Ocean (1933/34) which were stored at the British Museum (Nat. Hist.) are considered in this paper. In all this material 47 species of hydromedusae were found. Most of them are rather common in the Indian Ocean, only Phialidinum lomae and Aglantha intermedia are new to this sea. Velella velella, Oceania armata, Köllikerina omata, Phialidinum lomae and Eucheilota tropica are recorded from the Red Sea for the first time. Between the material of the "Meteor"-Expedition and the "John-Murray"-Expedition no fundamental difference appeared. The southequatorial current system seems to be richer in species than the northern systems. Off the Indian coast a relatively high number of species was found. 3089 specimen were counted in the Material of the "Meteor"-Expedition into the Arabian Sea. Aglaura hemistoma (60%), Solmundella bitentaculata (13%) and Liriope tetraphylla (12%) account for 85% of the individuals. No significant correlation seems to exist between the numbers of specimen in different regions and biotic and/or abiotic factors.

Description: The present study deals with 3 new genera and 14 new species of the Copepoda Harpacticoidea from the Peru-Trench and the Iberian deep-sea. The systematical position of the Argestigensgroup (Cletodidae) is discussed within the taxonomical remarks concerning the genus Parameiropsis n. gen.

Description: Description of Trefusialaimus monorchis nov. gen. nov. spec., Trefusiidae, characterized by only one testis, by seminal duct without differentiation of a muscular ductus ejaculatorius, and by pericloacal papillae. Second species of genus is T. magnus (FILIPJEV 1946), syn. Trefusia magna. With particular reference to the male genital apparatus Trefusialmus combines features of Dorylaimida Alaimina and Enoplida Tripyloidea.

Description: During the Indian Ocean Expedition of R/V "Meteor" phytoplankton samples were taken with a multiple closing net ("multinet") at 103 stations. In this material the diatoms were investigated. In all 247 taxa could be identified which belong to 242 species and 5 varieties or formae of 80 genera. Of these 1 variety, 15 species, and 3 genera are newly described. New combinations were made for 18 species, and a number of old combinations was reinstated. A distribution list of all species in the investigated area is included.

Description: 1. Three species of Crustacea Decapoda Reptantia are recorded from the Iberian deep sea basin, which belong all to Munidopsis. 2. A species highly characteristic of this basin was newly described under the name Munidopsis thieli. 3. For investigations on zoogeography of deep sea areas ultraabyssal species should be used.

Description: 1. Nine species of Crustacea Decapoda Reptantia were collected during cruise 26 of R. V. "Meteor". 2. Subspecific status is given to Ilia nucleus spinosa and Ilia nucleus nucleus and discussed in some detail. Both taxa were referred to as independent species up to this time. 3. The intermediate faunal character of the Mauretanian province is proved by the example of Cap Blanco. Further investigation is of need for getting complete evidence on the fauna of that area.

Description: Four new species of the genus Sphaerolaimus BASTIAN, 1865 are described: S. crassicanda sp. nov., S. ibericus sp. nov., S. hadalis sp. nov., S. peruanus sp. nov. These nematodes from the deep-sea were collected during cruise 8 of R. V. "Meteor" in the Iberian Deep-Sea in depths between 1311 m and 1944 m and during cruise 11 of R. V. "Anton Bruun" in the Peru-Trench in depths between 500 and 6300 m. A key to the genus is provided.

Description: Some Tardigrades were collected during the 1964/1965 R. V. "Meteor" cruise in the Indian Ocean. Thirty-nine specimens were gathered by H. THIEL from deep sea stations ranging from 1630 to 4690 m. These specimens included the types of a new family of Arthrotardigrada: the Coronarctidae, a preliminary description of which was given by RENAUD-MORNANT (1974). A complementary and detailed description of adults and larvae is given hereby and an attempt is made to insert this new family in the phylogenetical series of the order Heterotardigrada. A new genus of Halechiniscidae is established with the description of the type-species Euclavarctus thieli n. g., n. sp. The genus Pleocola CANTACUZÈNE, 1951 is recorded from two different stations and P. conifera n. sp. is described. The problem of the distribution of Tardigrada in abyssal depths is discussed on account of the occurrence of Coronarctus in both Indian Ocean and Atlantic Ocean, and of the new record of the genus Pleocola in deep water.

Description: On the cruises 3 and 15 of R. V. "Meteor" a number of benthic abyssal gastropods has been collected. Two of the species found in these samples belong to the subgenus Theta CLARKE, 1959 of the genus Pleurotomella. One of the species is Pleurotomella (Theta) lyronuclea CLARKE, 1959, hitherto only known by one single specimen from off Bermuda; CLARKE's description is completed, based on the additional specimens now available. The other one is a new species named Pl. (Theta) bathyiberica, which is described and photographed.

Description: The meiofauna of the deep sea areas (800-5500 m) between Madeira and Lisbon was quantitatively investigated during the "Meteor" cruises in 1970 and 1971. With respect to numbers and biomass the meiofauna (especially nematodes and harpacticoid copepods) of the investigated areas is relatively poor averaging about 66,000 individuals per m2 and 34 mg per m2 wet weight biomass (polychaetes and foraminifera excluded). Regional differences are more pronounced in the investigated areas than differences due to depths. A comparison with the results of other authors from other areas confirms the regional variations in the meiofauna abundance of the deep sea.

Description: Among the gastropod material taken by R. V. "Meteor" on the Great Meteor Bank during the seamount cruises in 1967, a new cymatiid species was found, resembling very closely the recently discovered Gyrineum louisae LEWIS, 1974 from off Hawaii. The new species - regarded as a sibling species to G. louisae - is described under the name Gyrineum atlanticum. Some comments are made on the validity of the genus Gyrineum LINK, 1807 and the zoogeography of the closely related species is discussed.

Description: Twentyone species of euthecosomes were present in the IIOE collections and most of them were very abundant in the upwelling and divergence areas such as the Somali coast, the South Arabian coast, the areas around India and Ceylon and off Java. The seasonal changes in the above areas were prominent. A gradual reduction in the number of species was found from South to North with the maximum (20) in the West Australian sea and minimum (12) in the northern Arabian Sea. L. lesueuri is named as the indicator of the subtropical watermass, C. globu­losa, the equatorial watermass and C. uncinata, the watermass around Andaman Islands. Ten patterns of distribution were traced with the biohydrographic boundaries at Bab el Mandeb, around Gulf of Oman, off central west coast of India, around 10° N, 10° S and 40° S. A distinct hydrological barrier found around 10° N has not only helped to explain the unique pattern of distribution in the north Indian Ocean but also supports the theory that the faunistic barrier exists in the open ocean.

Description: In this account 101 species of fishes derived from the bottom hauls on the shelves of the coast of Portugal and of Morocco, the Great Meteor Seamount, the Josephine Seamount and the Gettysburg Bank have been identified and arranged in systematic order. For all a few of the most relevant synonyms are mentioned, the material is enumerated and measurements are given under the stations it has been taken at. Only some of the most common and well-known species were not described, for others a short to detailed description is given, and some taxonomical and morphological points are discussed. The range of distribution of each species has been treated as comprehensively as possible. The stations, their dates, exact positions, depths and gear are given in a list.

Description: In 22 samples, 6 from the Josephine Bank and 16 from the Great Meteor Bank, 14 halacarid species were found and described. Halacarus spiniger n. sp., Copidognathus magniporus n. sp., Arbodeoporus lineatus n. sp., A. brevocularis n. sp., Coloboceras karamani n. sp., Scaptognathus minutus n. sp., and Atelopsalis newelli were hitherto unknown. Acaromantis squilla TROUESSART & NEUMANN and Atelopsalis tricuspis TROUESSART were redescribed. Four larvae, probably belonging to Copidognathus longipes BARTSCH, C. tricorneata (LOHMANN), Lohmannella falcata (HODGE), and Atelopsalis newelli n. sp. were described, two Scaptognathus larvae could not be identified. To date only three species, Copidognathus tricorneata, Lohmanella falcata, and Scaptognathus minutus, have been found on both seamounts.

Description: Among a macrofauna (madreporaria, spongia) from the Great Meteor Bank two halacarid species were found, Agatte alberti (TROUESSART) and Copidognathus raekor n. sp. The male, female and protonymph of Copidognathus raekor are described.

Description: This is an account of hydromedusae from the Red Sea and the Gulf of Aden. Only 12 hydromedusae were previously known from the Red Sea, 18 from the Gulf of Aden. About 500 plankton samples - from various expeditions and own collections near Eilat - were investigated. 76 species of hydromedusae were found, 72 from the Red Sea, 30 from the Gulf of Aden. Only 5 species in both the Red Sea (Zanclea costata, Aequorea aequorea, Liriope tetraphylla, Aglaura hemistoma and Rhopalonema funerarium) and the Golf of Aden (Bougainvillia fulva, Eutima modesta, Liriope tetraphylla, Aglaura hemistoma and Rhopalonema velatum) bad been found there by formet investigators. 10 species (Pachycordyle conica, Podocoryne meteoris, P. minima, Allorathkea ankeli, Bougainvillia muscoides, Thamnostoma eilatensis, Laodicea fertilis, Phialidium ambiguum, Eirene kambara, Helgicirrha schulzei) are recorded for the first time from the Indian Ocean. 6 different regions are distinguished in the area of investigation [Bay of Eilat (E); Gulf of Aqaba (A); northern Red Sea proper (S); Red Sea (R) without E, A, S, D; Dahlak Archipelago (D); Gulf of Aden (N)] and compared with regard to the hydromedusae fauna. There is an eightfold increase in the number of species from north to south. The diversity of Antho- and Leptomedusae increases towards the Dahlak Archipelago and decreases again towards the Gulf of Aden, whereas the Trachylina increase towards the Gulf of Aden with exception of the samples from the Dahlak Archipelago. Considering the distribution of the suborders, one finds the reduction of numbers in the Leptomedusae responsible for the low values of Hydroida in the Gulf of Aden. In the Trachylina both suborders - Trachymedusae and Narcomedusae - are equally responsible for the distribution pattern found. The Red Sca is considerably richer in species of hydromedusac than the eastern Mediterranean which is comparable only to the Gulf of Aqaba in respect of the poor number of species. The number of specimen per sample decreases from Eilat towards the northern part of the Red Sea proper and then varies about the average for all samples (26), with the exception of the Dahlak Archipelago, where great numbers of Liriope tetraphylla cause maximal density values. The pattern of distribution is dominated by the Trachylina, especially the Trachymedusae, Hydroida play the minor role. The most important Anthomedusae is Bougainvillia fulva which is responsible for the distribution pattem of Hydroida; within the Leptomedusae no single species is dominating. Aglaura hemistoma is the most abundant medusa, their numbers decrease markedly from north to south. Rhopalonema velatum has a maximum abundance in the northern part of the Red Sea and a minimum around the Dahlak Archipelago. Solmundella bitentaculata is responsible for the distribution pattern of Narcomedusae with two maxima in the Gulf of Aqaba and in the R-region. The remaining species increase in density from north to south, with exception of the somewhat lower values from the Dahlak Archipelago. Numbers of individuals seem to increase with water temperature in the Red Sea, number of species to decrease. With increasing salinity numbers of both species and specimens per sample decrease. Above 38‰ S all of these values are below the mean.

Description: Surface-living plankton of the subtropical NE-Atlantic (from 22° to 33° N and 28° W to the African coast) has been collected in winter 1970. Near the coast additional deeper hauls down to 50 m have been made. A modified David-Neuston sampler with two nets (300 or 500 μ mesh size) and a modified Gulf V sampler ("Langhai") with 300 μ were used. This paper deals with the ichthyoplankton only. A total of 14863 fishes or fish larvae were caught. They belonged to 51 different taxa. Between the neritic area (reaching to 130 nautical miles from the coast) and the oceanic area, great differences in the composition of ichthyoplankton were observed. The 27 neritic neuston samples yielded 110 less than 35 of the 51 taxa, while the 32 oceanic neuston samples had but 22 taxa, where of only 6 had not been caught in the first section. The average concentration of 190 fishes in 100 m3 of water filtered in the former area was significantly higher than in the oceanic area (112 individuals in 100 m3). The higher number of species near the coast is due to the fact that besides young stages of bottom-living and neritic pelagic fishes, mesopelagic species were caught. The neritic area showed higher surface temperatures, which normally brings a higher number of species. The species composition was not distinctly different with the results obtained in other seasons, but the percentage and the length distribution varied. The reason seems to be that the spawning of many species took place in this season. Young larvae of Macrorhamphosus, Scombridae, Carangidae and Sparidae have been caught in higher numbers. The following ecological aspects were observed in a part of the material. The distribution of some fishes, e.g. Mugilidae, indicate a preference to surface temperatures higher than 19°C. Sparids probably have the same temperature range. A large number of the ichthyoplankton showed a preference to the immediate surface for certain hours or even the whole day. For these species the daily rhythm was noted and an ecological grouping of the groups "euneuston", "daytime facultative neuston", "nighttime facultative neuston" and "pseudoneuston" was made. The "euneuston" includes all stages of Scomberesox, Mugilidae, Sparidae and the juvenile Carangidae. The "daytime facultative neuston" includes the juveniles of Macrorhamphosus and Scombridae together with the larvae of Ceratoscopelus. "Nighttime facultative neuston" are the young larvae of Macrorhamphosus and several genera of adult Mytophidae. "Pseudoneuston" includes mainly larvae of mesopelagic species as well as the larvae of Scombridae. For some taxa, a change in behaviour is probable. So early larval stages of Macrorhamphosus (up to 3 mm) and small Belone belong to the "nighttime facultative neuston", while elder stages should be regarded as "daytime facultative neuston" or "euneuston" in Belone. A change probably occurs in Scombridae and Carangidae too. Corresponding with this behavioural change in Macrorhamphosus a change in pigmentation from brown-white to blue seems to appear. A similar change may be assumed for Scombridae and Carangidae, but was not found in Belone.

Description: Additional comments on appendicularians found in unsorted parts of catches from the Arabian Sea are given. They concern: (1) specific differences between very young specimens of Oikopleura cornutogastra and 0. fusiformis; (2) the inclusion of LOHMANN's species Oikopleura mediterranea in the genus Folia which now comprises two species, F. gracilis LOHMANN 1896 and 0. mediterranea (LOHMANN 1899 n. n.); (3) the body form of very young Stegosoma magnum; (4) the occurrence of Appendicularia sicula FOL 1874 and (5) that of Kowalweskia oceanica LOHMANN 1899 in the area.

Description: With the increasing aging of an upwelling body of water, a pronounced rise in the saprophyte counts was found at first in the surface water and later also in the deeper zones. They increased, for example, at a depth of 15 meters, from 30-50 to 250 bacteria/ml, which represents a production of 4 X 10-3 mg bacterial C/m3 water. Different bacteria populations were included on the medium used for isolation, which was prepared with both sea-water and fresh water. On the former, which had relatively few species represented, the spectrum ranged from whitish to yellowish-white halophilic marine bacteria. On the tap water medium, however, dominated a spectrum of white or vividly pigmented bacteria, comprising many species, with maximal development in fresh water. It is supposed that bacteria of terrestrial origin are involved here, which are possibly carried to the sea by sand or dust storms. With regard to the colony forms, no difference between the bacteria populations within or without the upwelling water could be determined. The greatest bacterial infiltration of the sediment was found on the surface (between 16 X 103 and 80 X 103 bacteria/cm3). Already in the upper 2 cm, a strong reduction of the saprophyte count was determined, together with a relative increase of those bacteria which possess a greater range of ecological amplitude. The saprophyte counts on the sediment surface decreased with an increase of water depth. On 21 strains of bacteria isolated from the open waters, investigations were carried out on their morphological characteristics and the most important metabolic reactions.

Description: During the 19th cruise of the research vessel "Meteor" between Madeira and Lisbon 260 strains of aerobic heterotrophic bacteria have been isolated from sediment samples collected from different depths. These strains have been identified mainly as members of the genera Marinovibrio, Pseudomonas, and Bacillus. The majority of bacteria isolated from shallow areas (Josephine Seamount) were sea water media requiring Marinovibrio and Pseudomonas spp. but in sediment samples taken from depths exeeding 1000 m the probably terrestrial sporeforming Bacillus spp. predominated. Further investigations in the same region during the 23rd cruise of the "Meteor" demonstrated that about 30 to 50% of the sporeforming bacteria found in the sediment samples could be isolated from dormant spores in situ. The remaining more than 50% of sporeformers in the deep sea region examined are believed to be metabolic active cells.

Description: The zooplankton, collected in three microlayers with the use of a neuston catamaran during the cruise of R.V. "Meteor" in the subtropical Northeastern Atlantic Ocean in 1967 was studied with a view to the ecology of the calanoid copepod family Pontellidae and its position in the neuston association. The material comprises 8 species. Two of them, the abundant Pontella atlantica and Anomalocera patersoni may be used as indicator species for two different pontellid associations which were confined to special water types characterized by different ranges of surface temperatures. The biocoenotic structures in both of the species groups are to some extent - similar to those of the co-occurring communities of total invertebrate neuston. Because of this, pontellids are considered to be a useful help in studying principal changes in structures of zooplankton due to the hydrographic environment. All the pontellid species, their developmental as well as their mature stages, showed daily vertical migrations, but of different extent and distinctness. With the exception of Pontellina plumata their preference of the uppermost 10 centimeters, the "pleustal", was well-defined. Nevertheless, only Pontella atlantica can be considered an euneustonic form. There was little evidence that in the atea of investigations pontellids played a really important role in the zooneuston community; only in the oceanic part of the area, during the hours of strongest solar radiation around noon, they might perhaps gain some ecological importance as predators in the surface layer.

Description: research

Description: Scottia browniana (Jones 1850) Brady & Norman 1889 war bisher als einziger Vertreter der Gattung Scottia aus dem Quartär von Europa bekannt. Die Art wurde zuerst fossil in Sedimenten des Mittel- und Altpleistozäns gefunden. Später glaubte man, diese Art auch rezent nachgewiesen zu haben. Auffallende Unterschiede zeigten sich in den ökologischen Ansprüchen: Während die rezenten Exemplare nur in unmittelbarer Nähe von kalten Quellen vorkommen, fanden sich die Fossilien überwiegend in den wärmeren Abschnitten von interglazialen Ablagerungen. Diese Diskrepanz führte zur Untersuchung des Belegmaterials von den Typlokalitäten. Dabei stellte sich heraus, daß die rezenten Exemplare mit den fossilen artlich nicht identisch sind. Die rezente Art wird infolgedessen als Scottia pseudobrowniana n. sp. beschrieben. Ferner konnte ermittelt werden, daß Cypris tumida Jones 1850 sowie Bythocypris candonaeformis Schweyer 1949 ebenfalls in die Gattung Scottia zu stellen sind. Synonym mit Scottia tumida (Jones 1850) n. comb, ist Cyclocypris huckei Triebel 1941, während Cyclocypris triebeli Kempf 1967 mit Scottia browniana (Jones 1850) synonym ist. Ob Scottia candonaeformis (Schweyer 1949) n. comb, als selbständige Art oder als Synonym von Scottia browniana zu bewerten ist, muß anhand des Materials von der Typlokalität noch überprüft werden. Insgesamt sind nunmehr mindestens drei Scottia-Arten aus dem Quartär von Europa bekannt. Von diesen wurden Scottia browniana und Scottia tumida bislang nur in warmzeitlichen Ablagerungen des Alt- und Mittelpleistozäns nachgewiesen. Scottia pseudobrowniana ist überwiegend rezent bekannt, findet sich gelegentlich aber auch fossil in Quellkalken und Seekreiden des Jungpleistozäns und Holozäns. Entsprechend der Verbreitungskarte sollte Südosteuropa oder Asien als Ausbreitungszentrum der Gattung Scottia in Betracht gezogen werden.

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Description: Einige Ergebnisse zur Frage der pleistozänen Harzvergletscherungen werden mitgeteilt. Diese Ergebnisse, die bei einer geologischen Kartierung des oberen Odertales gewonnen wurden, erbringen den Nachweis, daß dieses Gebiet im Pleistozän vergletschert war. Die Geländeuntersuchungen im Odertal konzentrierten sich auf vier Endmoränenbögen und die mit ihnen verknüpften Ablagerungen, die in folgende geologisch-geomorphologische Einheiten untergliedert werden können: 1) Sander-Vorfeld, 2) Endmoränenlandschaft mit Blockwällen, Schmelzwasserrinnen und Toteislöchern, 3) Seitenmoränenlandschaft mit Kamesterrassen, Schmelzwasserrinnen, Toteislöchern, paraglazialen Teilfeldern und erratischen Geschieben, 4) Gletscherzungenbecken mit bis zu 23 m mächtigen, glazilimnischen Sedimenten.

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Description: Vom Geologischen Landesamt Schleswig-Holstein durchgeführte lagerstättenkundliche und bodenphysikalische Untersuchungen an marinen Tonen des Holstein-Interglazials erbrachten den Nachweis, daß es nach der Regression des Holstein-Meeres im terrestrischen Faziesbereich zur Entstehung eines Bodens (Humus-Orterde) und im limnischen Faziesbereich zur Bildung eines „Sumpftorfes" mit abschließender algenreicher Detritusmudde gekommen ist. Zwischen der marinen Tonserie und den organogenen Ablagerungen bzw. der Bodenbildung kann eine periglaziale Phase nachgewiesen werden, die sich in einer äolischen Akkumulation und in der Bildung von Froststrukturen (Kerkoboloide) ausdrückt. Aufgrund dieser Befunde und der von Menke (1968) festgestellten palynologischen Befunde läßt sich die Holstein-Warmzeit in ein älteres (Muldsberg-Warmzeit) und ein jüngeres Holstein-Interglazial (Wacken-Warmzeit) gliedern, das durch eine mehr oder minder lang andauernde bzw. kurzfristige Periglazialphase (Mehlbek-Kaltphase) zweigeteilt wird.

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Description: Die problematische Stellung der saaleeiszeitlichen Terrassenablagerungen der Werre, die sich aus der einschlägigen Literatur und den Geologischen Karten ergibt, veranlaßte den Verf. zu Terrassenuntersuchungen am Unterlauf der Werre bei Gohfeld und Bad Oeynhausen. Vor allem wurden der stratigraphische Aufbau der Ablagerungen untersucht und Rundungsmessungen an Quarzkörnern vorgenommen. Als Beispiel wird die Terrasse bei Gohfeld, Nähe Bahnhof, an der eiszeitlichen Einmündung des Sudbaches in die Werre näher beschrieben und klimatisch gedeutet. Im Hangenden des Terrassenkörpers befinden sich solifluidaler Wanderschutt bzw. Niederterrassenablagerungen, im Liegenden saaleeiszeitliche Sande und Kiese mit tieferreichenden Froststrukturen. Bei den Kiesen handelt es sich um nordische Feuersteine; die Porphyre und Granite stammen aus dem Thüringer Wald und sind daher ursprünglich von der Weser herantransportiertes, mehrfach umgelagertes Material. Die überwiegende Mehrzahl der Quarzkörner ist mittelmäßig gerundet und auf jeden Fall transportbeansprucht. Für eine einheitliche Fließgeschwindigkeit des Flusses und Akkumulation im Mittelterrassenkörper spricht die relativ gute Sortierung, denn Anzeichen für Staubeckenbildungen wurden bisher nicht gefunden. Zu Beginn der Saaleeiszeit lag die Talsohle der Werre bei Gohfeld im Lias etwas über dem Niveau der heutigen Talaue. Die Anknüpfungen der Terrassen des Werreunterlaufs an die saaleeiszeitlichen Flußablagerungen im Wesersystem konnten festgestellt werden.

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Description: Auf der Grundlage terrassenmorphologischer Untersuchungen im oberen Ampertal lassen sich neben dem rezenten Ammerseespiegel von 533 m NN alte Seespiegel bei 565 m, 561 m, 555 m, 544m, 542 m und 536m rekonstruieren. Die Datierung dieser Seespiegel ergibt sich aus morphologischen und pedologischen Beobachtungen, wobei die zwei höchsten Wasserstände keinem Seespiegel, sondern einem Gerinne auf Toteis entsprechen. Die Absenkung von 565 auf 561m NN erfolgte nach dem Ammerseestadium, die folgende auf 555 m NN an der Wende vom Hoch- zum Spätglazial, wobei der Seespiegel von 536m NN sehr wahrscheinlich erst in der Jüngeren Dryas erreicht wurde. Die Zerschneidung der Endmoränen und damit die Erniedrigung des Ammerseespiegels hat vermutlich sehr viel länger gedauert, als bisher angenommen wurde.

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Description: Korngrößen-, Kies- und Schwermineralanalysen würmzeitlicher Grundmoränen-Ablagerungen des Rheingletschers im baden-württembergischen Alpenvorland zeigen einen meist relativ niedrigen Einfluß des aus Molasse bestehenden Substrats auf die Zusammensetzung dieser Sedimente. Auf Grund theoretischer Überlegungen und großmorphologischer Beobachtungen wird geschlossen, daß auch die Aufnahme präexistierender quartärer Ablagerungen untergeordnet war und daß die Petrographie der Moränen-Ablagerungen hauptsächlich bestimmt wird vom während der letzten Vorland-Vergletscherung vom Rheingletscher ins Vorland transportierten Schutt.

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Description: Eisrandsysteme sind bedeutende paläogeographische Archive, die die Vereisungsgeschichte in marinen und kontinentalen Becken aufzeichnen. Im Fokus dieser Arbeit stehen saalezeitliche, glazilakustrine Eisrandablagerungen des Weser-und Leineberglandes, die in etwa die maximale Ausdehnung des saalezeitlichen Drenthe-Eisschildes markieren. Die Faziesarchitektur und die internen Deformationstrukturen dieser Eisrandablagerungen werden in Hinblick auf Gletscherdynamik, hochfrequente Seespiegelschwankungen und Basement-Tektonik diskutiert. In den letzen 10 Jahren haben wir im Weser- und Leinebergland 27 Kies- und Sandgruben neu bearbeitetet und mehr als 4000 Bohrungen ausgewertet, um die saalezeitliche Sedimentation im Bereich des Eisrandes und der vorgelagerten Seebecken zu rekonstruieren. Die Geländearbeiten wurden durch Scherwellenseismik-Profile ergänzt. Basierend auf diesen Daten wurden mit Hilfe von digitalen Höhenmodellen und geographischen Informationssystemen (GIS) saalezeitliche Eisstauseen im Weser- und Leinebergland rekonstruiert. Wir vermuten, dass die Bildung und das katastrophale Auslaufen dieser tiefen Eisstausseen die Stabilität des drenthezeitlichen Eisschildes stark beeinflusst und möglicherweise den Hondsrug Eisstrom initiiert haben. Unsere Studie zeigt darüber hinaus, dass der elsterzeitliche Eisschild vermutlich nicht weiter als der drenthezeitliche Eisschild nach Süden vorgedrungen ist, als bisher angenommen wurde.

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Description: Mineralische Rohstoffe werden in großen Mengen für die verschiedensten Wirtschaftszweige benötigt. Die Gewinnung oberflächennaher Rohstoffe bedingt i. a. eine Abbaugrube, welche später wieder in die Umgebung eingefügt, d. h. rekultiviert oder renaturiert, werden muß. Im Zuge eines erstarkenden Umwelt- und Ökologiebewußtseins ist der Renaturierung verstärkte Aufmerksamkeit zu schenken.

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Description: Verschieden alte, datierte Böden auf den Niederterrassen des Rheins werden mikromorphologisch charakterisiert und ausgewählte Merkmale dem Bodenalter gegenübergestellt. Klare Beziehungen zum Alter zeigen. Entkalkung und Tonwanderung. Bereits in der Gruppe der 1800jährigen Böden wird eine Entwicklung sichtbar. Ab 6000 Jahren kommen Parabraunerden vor. Stark entwickelt sind die Böden auf präholozänen Sedimenten. Die Bodenbildung in situ wird vom Wechselspiel aus Bodenentwicklung und -abtrag im Liefergebiet der Sedimente mitbestimmt. Die im Liefergebiet begonnene Silicatverwitterung läuft in der Aue weiter, während die Horizontdifferenzierung durch Tonverlagerung nach dem Transport in der Aue neu beginnt. Die Böden aus präholozänen Sedimenten können kurzstreckig verlagertes Material von Bt-Horizonten eemzeitlicher Böden enthalten. Die systematische Stellung der Böden wird diskutiert. Die Bedeutung der Tonwanderung zwischen Sandkörnern wird anhand verdichteter Böden des Versuchsgutes Wahn dargestellt.

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Description: Seit 100 Jahren werden Ablagerungen in Norddeutschland als vom Inlandeis hinterlassen angesehen. Der Wechsel der Auffassungen über das Geschehen am Eisrand sowie der heutige Stand der Erkenntnis werden dargelegt. Hervorgehoben wird: Fels- und Lockerboden als Untergrund bedingen verschiedenes Verhalten des Eisrandes. Widerlager wie Stauchmoräne und Hochsander erzwingen das Aufsteigen auch der tiefsten fließenden Eislagen. Schwankungen des Eiszuflusses bedingen Zu- und Abnahme der Mächtigkeit des Eises am Widerlager, aber keine Änderung der Lage des Eisrandes. Bei starkem Zufluß schiebt das Eis das Widerlager beiseite. Die noch jüngst vertretene Anschauung vom „Überfahren" des Widerlagers wird aus mehreren Gründen abgelehnt. — Tunneltäler entstehen durch kleine Eiszungen, die dort auslaufen, wo der Ausfluß in- oder subglazialer Wässer das Widerlager abgetragen hat.

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Description: Die modernen Anforderungen an den Trinkwasserschutz, die zunehmende Zersiedelung und die landwirtschaftliche Nutzung weiter Teile der Niederrheinischen Bucht führen immer häufiger zu Nutzungskonflikten. Da die einmal vorhandenen Nutzungsstrukturen wie Naßabgrabungen und Gewerbegebiete die Flächen für eine schutzfähige Grundwassergewinnung reduzieren, bleibt oft nur die Verlagerung der Trinkwassergewinnung in zuvor nicht beanspruchte Gebiete. Am Beispiel einer Prognose für die Verschiebung einer Entnahmegalerie aus einer Zone mit gewerblicher und lagerstättentechnischer Nutzung im Umfeld des Xantener Stauchmoränenbogens kann gezeigt werden, daß auf der Grundlage quartärgeologischer Grundlagendaten und eines numerischen Grundwasserströmungsmodells eine Optimierung der Ortslage für eine Trinkwassergewinnung durchgeführt werden kann. Die eiszeitliche Überprägung weiter Teile des hydrogeologischen Grundwasserleitersystems im Xantener Bogen bedingte zahlreiche Restriktionen für die Optimierung eines Grundwassergewinnungsbereichs. Mit Hilfe der Geländeaufnahmen und der Modellrechnungen wurden verschiedene neue Brunnenstandorte simuliert und hinsichtlich der ökologischen und hydrogeologischen Restriktionen bewertet. Die Modellrechnungen ermöglichten bereits im Planungsstadium eine Vorausschau auf die Auswirkungen und den Nutzen einer Verlagerung der ursprünglichen Entnahmeschwerpunkte. Die Ergebnisse zeigen aber auch, daß ein Ausweichen der Trinkwassergewinnung zugunsten anderer Flächennutzungen mit neuen Restriktionen am neuen Standort verbunden sein kann und somit in jedem Einzelfall zu überprüfen ist.

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Description: Schotterpetrologische Untersuchungen im Aaretal südlich von Bern zeigen, daß die petrologische Zusammensetzung der Fraktion 〉 2 cm von älteren zu jüngeren Schotterakkumulationen gesetzmäßig ändert. Die ältesten, bis jetzt nachgewiesenen pleistozänen Schotter im Aaretal, die Bümbergschotter, sind reich an aufgearbeitetem Mollassematerial (〉15 %), welches in den letzteiszeitlichen Münsingenschottern, bzw. spätglazialen Wichtrachschottern 〈10% beträgt (Abb. 2). Bei den Münsingenschottern (Obere und Untere als Einheit betrachtet) kann östlich und westlich des heutigen Aarelaufes eine verschiedene Fazies in der Geröllführung nachgewiesen werden (Abb. 3). Das von Cadisch (1928) beobachtete Widerspiegeln der Heraushebungs- und Erosionsgeschichte des Alpenkörpers in der Petrologie der Molassesedimente gilt auch für die petrologische Geröllzusammensetzung der mittel- bis jungpleistozänen Schotterakkumulationen.

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Description: Zwei Torfvorkommen in der Altmoräne des westlichen Rheingletschergebietes, beide auf sicher rißeiszeitlichen Ablagerungen und überdeckt von würmglazialen Fließerden, werden untersucht und palynologisch bearbeitet. Sie gehören mit hoher Wahrscheinlichkeit ins Riß-/Würm-Interglazial. Von keinem der beiden Vorkommen liegt ein vollständiges Pollendiagramm vor.

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Description: Es wird der bislang vollständigste Einblick in die Schicht- und Lagerungsverhältnisse der Kiesgrube von Hörmating/Obb. geboten und dazu die Darstellung und Deutung durch Ebers (1960, 1963, 1965), Gross (1960), Kraus (1961) und Brunnacker (1962) kritisch beleuchtet. Die beiden mächtigen fossilen Böden entstanden in keinem Falle in Interstadialabschnitten der Würmeiszeit („Göttweig", „Paudorf"), sie gehören vielmehr in echte Interglazialzeiten, und zwar des prärißeiszeitlichen Mittelpleistozäns.

Description: research

Description: In einem kleinen Lager im Tiefland bei Kitros (Makedonien) werden fluviale Bildungen durch kolluviale Sedimente und einige Meter Löß mit fossilen Böden überdeckt. Trotz der makro- und mikromorphologisch sehr ausgeprägten Böden werden die Deckschichten gemäß der allgemeinen Geländesituation, wie der Details im Profilaufbau in die Würmeiszeit gestellt. Die vier fossilen Böden sind weitgehend an Kalk verarmt, sie sind sehr tonreich und zeigen ausgesprochen verdichtetes Gefüge. Die typologische Ansprache als „rote Mediterranböden" kann vorerst allerdings nur eine Arbeitsbezeichnung sein. Der tiefste dieser Böden wird dem Zeitabschnitt Amersfoort- bis Broerup-Interstadial, der oberste dem Stillfried B zugeordnet. Gleichartige Vorkommen wurden außerdem bei Xanthi und in der nördlichen Türkei gefunden. Damit zeichnet sich eine eigenständige Löß- und Paläobodenprovinz ab. Feuchtere bzw. wechselfeuchtere Phasen werden darin durch die Böden angezeigt. Diese sind einem Ablauf zwischengeschaltet, der trockener war, der insbesondere — wie auch sonst — gegen das Hochglazial hin durch aridere Bedingungen bei erheblich abgesenkten Temperaturen ausgezeichnet war.

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Description: Die Formengemeinschaft der Hochgebiete des Bayerischen Waldes ist oberhalb von etwa 1 000 m Höhe gekennzeichnet durch die Vergesellschaftung von Karen, Steilhängen, steilen Muldentalschlüssen, bandförmigen Hangversteilungen sowie Wasserfällen und Flußschnellen. Diese Formen kommen auch unterhalb der in der Literatur aufgeführten mächtigen Blockmoränen vor und sind Zeugnisse einer weitreichenden Vergletscherung. Die C14-Bestimmung einer Probe aus dem Grundmoränenkomplex im Aufschluß bei der Schustersäge im Reschwassertal gab ein Alter von etwa 40800 Jahren. Es lassen sich drei würmeiszeitliche Stadien unterscheiden: das Maximalstadium, das Blockmoränenstadium und das Karmoränenstadium. Die Schneegrenzen der Stadien betrugen etwa 1060, 1140 und 1230 m. Im Regengebiet bei Zwiesel gibt es Aufschlüsse mit Stauchungserscheinungen in hochgelegenen Terrassen. Diese Vorkommen sind älter als die letzte Eiszeit und werden entsprechend den Befunden im Schwarzwald als Spuren einer noch ausgedehnteren rißeiszeitlichen Vergletscherung gedeutet. Die Karte der Verbreitung der würmeiszeitlichen Gletscher gibt für die tschechischen Gebiete nur eine extrapolierte Verbreitung an, die auf Grund von Karteninterpretationen entstand und nicht im Gelände überprüft werden konnte.

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Description: Die Deckschichten-Profile der Rheinterrassen unterhalb Kölns zeigen prinzipiell den gleichen Aufbau, wie er aus dem nördlichen Alpenvorland bekannt ist. Auf der Krefelder Mittelterrasse tritt Löß einer nachfolgenden Kaltzeit auf (z. B. Holzheim). Die Untere Mittelterrasse trägt Deckschichten von zwei jüngeren Kaltzeiten (Giesenkirchen). Auf der Jüngeren Hauptterrasse liegt eine reich gegliederte Abfolge, welche den Deckschichten über den sogenannten Riesenböden von Regensburg (K. Brunnacker 1964a) verwandt ist — also vier Kaltzeiten vertritt, von denen die älteste weiter unterteilt ist (Wegberg).

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Description: Die quartäre Grabenfüllung des nördlichen Oberrheintales baut sich aus den petrographisch gut unterscheidbaren, fluviatilen Sedimenten von Rhein, Main und Neckar auf. An der Oberfläche dieser fluviatilen Ablagerungen kam es im Jungpleistozän und Holozän zur Bildung von Flugsanddecken verschiedener Mächtigkeit und Ausdehnung; auf größeren Flächen wurden die Flugsande zu Dünen unregelmäßiger Form und Anordnung aufgeweht. Die verschiedene petrographische Ausbildung dieser Flugsande machte eine Abgrenzung folgender Flugsand-Faziesräume notwendig: 1. Das Maingebiet mit seinen mittel-grobkörnigen und meist kalkfreien Flugsanden. 2. Die Bergsträßer Flugsandvorkommen, in denen feinkörnige, kalkhaltige äolische Sedimente überwiegen. 3. Das Lorsch-Viernheimer Dünengebiet, dessen Flugsande sich von denen des Bergsträßer Raumes nur wenig unterscheiden. 4. Der Sprendlinger Horst mit seinen, den Mainflugsanden petrographisch ähnlichen, äolischen Sedimenten. Die vollständigste Profilentwicklung war im Maingebiet zu beobachten. In diesem Raum überlagern die äolischen Deckschichten, wie die eingehende Untersuchung der fluviatilen Ablagerungen deutlich gezeigt hat, auf großen Flächen die Reste eines letztinterglazialen Bodens an der Oberfläche der alt- bis mittelpleistozänen Kelsterbacher Terrasse. Gelegentlich sind Flugsande und Dünen auch auf den geringmächtigen Ablagerungen einer vermutlich Oberen Niederterrasse verbreitet, besonders wo diese randlich auf die Kelsterbacher Terrasse übergreift. Aus dem Profilaufbau der Dünen im Maingebiet läßt sich, teilweise in Anlehnung an die Lößstratigraphie, folgender Geschehnisablauf rekonstruieren: Auf den, der fluviatilen Akkumulation entzogenen, älteren Terrassenflächen überwogen im Frühwürm intensive Abtragungs- und Verlagerungsvorgänge. Am Ende dieses durch kühlfeuchte Klimabedingungen gekennzeichneten Zeitabschnittes dürfte die Bildung der lehmstreifigen Basiswechselfolge der Dünen erfolgt sein. Über den, durch einen schwer einstufbaren (W I/II?), geringmächtigen Kryoturbationshorizont nach oben begrenzten Basisschichten folgt die Hauptmasse der, meist mehrere Meter mächtigen, Dünensande. Diese im tieferen Teil stellenweise durch einen schwach ausgeprägten Naßfleckenhorizont (W II/III?) gegliederte Flugsandabfolge dürfte stratigraphisch dem Würm III-Löß der hessischen Gliederung entsprechen. Die unter den besonderen Klimabedingungen des Spätglazials auf diesen Dünensanden einsetzende Bodenentwicklung führte bis zum Alleröd-Interstadial bereits zur Bildung von Sandparabraunerden (Bänderflugsande), während im Vergleich dazu auf den jüngsten Lößdecken stellenweise schwach ausgeprägte Parabraunerden entstanden. Durch die Einlagerung einer im Mittel-Alleröd (Laacher-See-Ausbruch) gebildeten Bims-Tuffschicht im Hangenden der Bänderflugsande ist eine absolute Zeitmarke gegeben. Die Verwitterung der mit Flugsanden vermischten Bims-Tuffe zu einem braunerdeartigen Boden begann vermutlich noch während des Alleröd-Interstadials. Aus den während des Kälterückschlages in der Jüngeren Tundrenzeit gebildeten Flugsanden entstanden unter dem Einfluß des postglazialen Klimaoptimums tiefgründige Braunerden, stratigraphisch vergleichbar den Steppenböden aus Löß im benachbarten Rheinhessen sowie den Lockerbraunerden der hessischen Mittelgebirge. Diese Bodenentwicklung wurde, wie durch paläolithische Funde und die C14-Bestimmung an Holzkohlen aus einer Brandschicht nachgewiesen werden konnte, im 6.—7. Jahrh. n. Chr. durch eine letztmalige stärkere Flugsandaufwehung beendet. Die jüngsten Flugsande sind auf den Dünen meist nur schwach verwittert. In einem besonderen Abschnitt wurden Fragen der Entstehung der für Sande charakteristischen Bänderung (Sandparabraunerde) erörtert. Bei diesen Bändern handelt es sich, wie aus den Befunden eingehender Untersuchungen hervorging, um meist dünne Ton-Eisenanreicherungshorizonte; das eingeschlämmte Material entstammt wahrscheinlich im wesentlichen nicht überlagernden Bv-Horizonten, sondern dem Sediment selbst. Die Verlagerung und Anreicherung der mobilisierbaren Substanzen dürfte sowohl mechanisch als auch durch die Einwirkung chemischer Prozesse erfolgt sein. Wie aus den stratigraphischen Untersuchungen hervorging, lag die Hauptbänderbildung bereits vor dem Alleröd-Interstadial; unter gegebenen Bedingungen kann es jedoch auch heute noch zur Bänderbildung kommen.

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Description: Die sandige wie die tonige Wattfazies des Küsten-Holozäns im ostfriesischen Küstengebiet zeigt in ihren Ablagerungen einen zyklischen Aufbau. Die Zyklen in den Ablagerungen der tonigen Wattfazies sind mit biostratigraphischen und geochronologischen Daten belegte lithostratigraphische, die in denen der sandigen Wattfazies nur undatierbare lithostratigraphische Einheiten (Tab. 1). Zur Erlangung von Altersangaben und damit der Möglichkeit einer zeitlichen Gleichsetzung der Zyklen in sandiger mit denen in toniger Wattfazies werden Kontaktstellen mit biostratigraphisch und geochronologisch datierten Zyklen bzw. Schichten benutzt. Als Ergebnis wird das „Arbeitsmodell" einer lithostratigraphischen Gliederung der zyklisch aufgebauten Ablagerungen der sandigen Wattfazies vorgelegt, das einen zeitlichen Vergleich mit den Ablagerungen in toniger Wattfazies erlauben soll (Tab. 2).

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Description: In der Höhle Reichentalloch bei Hirschbach fand sich eine Fauna mit 33 Arten, darunter Anuren bis 38%. Die Fauna konnte in einen frühpostglazialen Auftauabschnitt gestellt werden. Auch konnte innerhalb derselben auf eine Durchwanderung von Pitymys subterraneus hingewiesen werden. Es wurde ein Diagramm-Auszug angefügt, entnommen einem großen Faunen-Diagramm, das aus den bisher in dieser Folge bearbeiteten, prozentual berechneten, ungestörten 30 Fundstellen mit 120 Schichten zusammengestellt worden ist, um die seltenen, aber auffälligen Anuren-Anhäufungen, daselbst eingereiht, als Auftauperioden zu erkennen, wie sie jeder Kältezeit folgten. Auch wurde eine Durchwanderungszeit von Microtus gregalis, der sibirischen Zwiebelmaus, aufgezeichnet; vermutlich auf der Flucht vor der einsetzenden Warmzeit.

Description: research

Description: Ein aus Kiesen und Sauden der Leine-Niederterrasse gebaggerter Schädel eines Steppeniltis (Mustela [Putorius] eversmanni soergeli Éhik) wird zum Anlaß genommen, die stratigraphische und ökologische Aussagekraft dieser Iltis-Art zu überprüfen. M. eversmanni ist in Mitteleuropa bislang mit Sicherheit nur aus verschiedenen Zeitabschnitten des Würm bekannt geworden, nie aus älteren oder jüngeren Schichten. In der Gegenwart ist der Lebensraum des Steppeniltis ziemlich streng an die Halb- bzw. Kultursteppe und an die Vollsteppe gebunden, wobei die wärmeren Teile des eurasiatischen Steppengürtels bevorzugt werden. Auch während des Würm kann die Art nicht unter wesentlich anderen Umweltsverhältnissen gelebt haben. Es wird daraus gefolgert, daß es auch in den Stadialen nicht nur trockenkalte, sondern auch trockenwärmere Phasen gegeben hat.

Description: research