ForewordOpening AddressList of ParticipantsPrevious SymposiaPopulation Cycles Annual Phytoplankton Successions in a Coastal Area in the Northern Baltic Fluctuations in the Abundance of Phytoplankton on the California Coast The Annual Cycle of Macrozoobenthos: Its Community Structures under the Influence of Oxygen Deficiency in the Western Baltic Annual Dynamics of a Northern Baltic Soft Bottom Rates of Change: Measures of Cyclic Stability among Communities of Taxocenes Density and Diversity of Meiobenthic Copepods: The Oscillatory Behavior of Population and Community Parameters Long and Short-Term Population Trends in the Polychaete Genus Nephtys Seasonal Recruitment and Population Structure of Co-Existing Mud Snails (Hydrobiidae) in the Baltic Sea The Annual Cycles of Two Species of Onchidoris (Opisthobranchia: Nudibranchia) Population Cycles Caused by Inter-Age, Density-Dependent Mortality in Young Fish and Crustaceans Indicator Copepods and Oil Yield Fluctuations in Pelagic Fish in the Benguela System Cyclic Fluctuations in Population Density during Eleven Years Recolonization of Rocky Shores in West Cornwall following the 'Torrey Canyon' Oil Spill in 1967 Changes in Littoral Populations as Recorded by Long Term Shore Surveillance. I. Selected Examples of Cyclic ChangesRhythmic Aspects of Reproduction and Growth Abundance and Lifecycle of Littoral Marine and Brackish-Water Tubificidae and Naididae (Oligochaeta) Experimental Studies on the Life Cycle and Production of the Littoral Oligochaete Lumbricillus lineatus, and Its Response to Oil Pollution Seasonal Changes in Populations of Nereis diversicolor O.F. Müller from the Severn Estuary, U.K. Adaptation and Reproductive Cycle of the Harpacticoid Copepod Amonardia normani (Brady 1872) in Semi-Enclosed Lagoons of Arcachon Bay, France Pattern and Strategy in the Reproductive Cycles of Benthic Harpacticoid Copepods Seasonal Changes in Dab (Limanda limanda) in Isle of Man Waters A Seasonal Fluctuation in Growth Rate of Young Plaice (Pleuronectes platessa) and Sole (Solea solea) in the Laboratory at Constant Temperatures and a Natural Daylight Cycle Effects of Non-Circadian Light Cycles on the Survival and Development of Palaemon elegans Rathke Reared in the Laboratory Cyclical Fluctuations in the Growth Rate of Stressed Hydroid Colonies The Cycle of Activity in the Accessory Nidamental Glands from Cephalopods Neurosecretory Regulation of Oogenesis in the Bay Scallop, Argopecten irradians irradians (Lamarck) Comparison of Events in the Seasonal Cycle For Donax vittatus and _D. trunculus in European Waters Seasonal and Annual Variations in the Allometric Relationships of Shell and Soft-Body Characters of Patella vulgata L. Seasonal Cycles in the Body and Shell Components of Lepidochitona cinereus (L.) Reproductive Ecology of Deep Sea Ophiuroids from the Rockall Trough Seasonal Reproduction in Deep-Sea Fish Changing Enzyme Activities in Maturing Gonads of the Winter Flounder, Pseudopleuronectes americanusCyclical Aspects of Production and Metabolism Seasonal Cycles of Decomposition and Production of Organic Material by the Benthos of a Semi-Enclosed Bay Primary Production and Nitrogen Cycling in an Estuarine Environment Studies on Nitrifying Microorganisms of the Eden Estuary, Scotland Seasonal Variation in the Respiratory Rate and ETS Activity of Deep-Water Zooplankton from the Swedish West Coast A Seasonal Survey of the Lipids in Calanus helgolandicus Claus from the English Channel The Influence of Seasonal Changes on Energy Metabolism in Mytilus edulis (L.). I. Growth Rate and Biochemical Composition in Relation to Environmental Parameters and Spawning The Influence of Seasonal Changes on Energy Metabolism in Mytilus edulis (L.). II. Organ Specificity L'aspartate transcarbamylase, indice de l'activité sexuelle de la coquille Saint-Jacques (Pecten maximus L.): premier résultats Diurnal Oxygen Consumption and Activity of Two Pontoporeia (Amphipoda: Crustacea) Species Adaptations of Corystes cassivelaunus to an Arenicolous Mode of Life In Situ Recordings of Oxygen Consumption Rhythms in Carcinus maenas An Unusual Respiratory Rhythm in the Crab Ebalia tuberosa (Pennant) (Crustacea: Decapoda: Leucosiidae)Rhythmic Behavior and its Control by Environmental and Physiological Factors Vertical Migrations of the Intertidal Dinoflagellate Amphidinium herdmaniae Kofoid and Swezy The Importance of Tidal and Day and Night Cycles in the Distribution of British Asterinids Some Properties of the Tidal Activity Rhythm in the Estuarine Amphipod Corophium volutator Adaptations Shown by Foraging Shorebirds to Cyclical Variations in the Activity and Availability of Their Intertidal Invertebrate Prey Diurnal and Seasonal Changes in the Timing of Peak Catches of Nephrops norvegicus Reflecting Changes in Behavior Diurnal and Horizontal Variations in a Zooplankton Sound Scattering Layer Seasonal Changes of Daily Vertical Migrations in a Supra-Benthic Cold-Layer Shelf Community Over Mud in the Gulf of St Lawrence A Circadian Hatching Rhythm in Nephrops norvegicus (Crustacea: Decapoda) Egg-Hatching Rhythms in Three Species of Fiddler Crabs A Semi-Lunar Rhythm of Locomotor Activity and Moult Synchrony in the Sand Beach Amphipod Talitrus saltator Swimming Rhythms, Migration and Breeding Cycles in the Estaurine Amphipods Gammarus chevreuxi and Gammarus zaddachi Time Cues for Semi-Lunar Reproduction Rhythms in European Populations of Clunio marinus. I. the Influence of Tidal Cycles of Mechanical Disturbance Cyclic Temperature Fluctuations in a Tidal Mud-Flat Physiological Control of Short-Term Cyclic Activities in Opisthobranch Molluscs Rhythmic Cycles of Blood Sugar Concentrations in the Crab Carcinus maenas The Role of Hanström's Organ in Clock Control in Carcinus maenasAbstracts of Poster Demonstrations Cyclic Behavior of Burrowing Fish Studies on Capitella capitata The Effect of Two Different Photoperiods on the Occurrence of Macro- and Micro-Thalli in the Life Cycle of the Brown Alga Colpomenia sinuosa from the French Mediterranean Coast Studies on the Regulation of Gametogenesis and Reproduction in Polychaete Worms Short-Term Variations in Phytoplankton Biomass in a Tidal Estuary in Northern Brittany Acides nucléiques et enzymes digestives au cours du développement chez Palaemon serratusAuthor IndexSubject Index