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Observations in a mangrove lined coast in south-western Puerto Rico (rainfall 800-1,000 mm; evaporation 1,900-2,200 mm; mean annual temperature 25º C; and average tidal range 0.3 m) have shown that the degree of structural development of the mangrove forest is closely related to wave exposure. In exposed coastal segments, sand berms formed by wave action within the outer fringe prevent water flow towards the inner forest, resulting in high salinities. The berms are higher in areas where the outer mangrove fringe has been destroyed by storms or other causes. Dead mangrove stands are found behind these areas and salinities reach 75-80‰ We suggest that the mangrove fringe contributes to dissipate wave energy over a broad area which reduces the high of the berm. The presence of absence of "blowholes" in the seagrass Thalassia; bed is an index of the degree of protection that the coast receives. The "thickness" of the mangrove fringe is also related to the degree of shelter: it is "thin" in high energy segments, "thick" in coastal segments subject to intermediate energy and "thin"again in the most sheltered locations. In the outlying cays mangrove development follows a similar pattern: the outer exposed cays (essentially coral islands mantled by coarse sands) are devoid of mangrove cover or have stunted trees (generally Laguncularia; canopy height, 2 m). Islands which are less exposed are colonized by Rhizophora which frequently forms overwashed forests (canopy height, 8-9 m). In the most seltered areas, Rhizophora colonizes the shallow banks, forming islands which soon develop an inner hypersaline lagoon due to the accumulation of material in the outer edges and the accumulation of salt in the interior. The wave energy level reaching a given section of the coast is therefore an important factor which determines the degree of structural development of the mangrove forest. High energy levels are associated with erosion, destruction or deposition of berms which affect mangrove development. Low energy levels, however, are associated with a rapid process of island maturation, aging and death due to rapid salt accumulation.

The studied area is limited by São Francisco River mouth, to the South, and by Coroa das Lavadeiras, State of Rio Grande do Norte, to the North. This area presents only two seasons, summer and winter. During the summer, the freshwater inflow is smaller, the southeast winds are dominant, the temperature, the salinity and the transparence of water are high. The winter is characterized by greater freshwater inflow, east winds, smaller temperature and low salinity and transparence only in coastal and estuarine waters. Off São Francisco River mouth the water conditions are inverted and the salinity and transparence variations affect all continental shelf. In the soft bottoms are found the following communities: a) Supralittoral beach; 2) Mediolittoral beach; 3) Infralittoral beach; 4) Circalittoral mud (São Francisco mouth); 5) Circalittoral gravel mud (São Francisco mouth).

In the rocky and gravely bottoms there are endolithic and epilithic species, and some soft bottom species. It was possible to distinguish in these bottoms the following communities: 1) supralittoral rock; 2) upper mediolittoral rock; 3) lower mediolittoral rock; 4) infralittoral rock; 5) infralittoral gravel; 6) circalittoral rock; and 7) semi-obscure caves.

This paper presents a list of crustacean decapods occuring in the State of Maranhão coast, Brazil, based on the study of collections of the Departamento de Oceanografia (Universidade Federal de Pernambuco) and Laboratório de Hidrobiologia (Fundação Universidade do Maranhão) and on litterature records. There are recorded 149 species (37 species of Natantia and 112 species of Reptantia).

The present paper is the first of a series dealing with marine zoogeography of Brazil. The Brazilian marine fauna has been well worked only recently, and the contributions on the zoogeography of various groups are in dependence of conclusions of faunistic surveys. Since Dana (1852) to present, various authors have divided diversely the littoral in natural regions, according temperature, salinity and species ranges. In the present paper the littoral between French Guiana and North Argentina was divided in 26 strips 2º wide, each strip extending from the coast to the 200 m isobath. The temperature and salinity data (surface and bottom) collected in each strip by Oceanographie Ship "Almirante Saldanha" were gathered in order to calculate the mean temperature of extreme months and the corresponding salinities (other data were also used, when necessary). The species list of each strip was made with the previously published records and the data of research institution files. The distributional data for the hermit crab were analysed in three ways: horizontal distribution; bathymetric range and substrate preferences. It was possible to divide the study area in five provinces (Guyanian, Brazilian, St. Paul's, Uruguayan and Argentinian); the St. Paul's Province is a transition zone between Tropical and Anti-Boreal Regions.

In the present paper the echo-sounding use accomplished by fishery boats for demersal species in the Rio Grande do Sul littoral is discussed. Considerations on the best use are made, including the need of more adequate echo-sounders and the training of the skeepers in echo-sounding techniques.

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Caloric values, ash and hydric percentages were obtained from the most abundant benthic invertebrates of Corral Bay, from which this information was not previously available. The range of these values is not different to those of related taxonomic groups of other oceans. Annual fluctuations of these paramenters were studied in Mytilus chilensis so as to obtain a quantitative estimation of the variation of these values.

This paper reports a quali - and quantitative study on phytoplankton occuring in the estuary of Igarassu river (Lat. 7º 49'S-34º 52'W), one of the most important in the Itamaracd region (50 km north of Recife, PE, Brazil). Samples were taken during the period May, 1973 to May, 1974. Forty two species of diatoms were identified and listed, representing the most frequent group of the marine microalgae collected. Special emphasis is given to the ecological conditions of the estuary.

This paper deals with the decapods crustaceans from Restinga island (Paraíba State, Brazil). A list of species collected from September 1977 to March 1978 and some ecological notes are given. Those following species were found in the island: Macrobrachium acanthurus (Wiegmann). Alpheus heterochaelis Say, Upogebia omissa Gomes-Corrêa, Petrolisthes armatus (Gibbes), Clibanarius vitatus (Bose), Clibanarius sclopetarius (Herbst), Callinectes danae Smith, Callinectes exasperatus (Gerstaecker), Callinectes bocourti. A.Milne Edwards, Callinectes sp., Panopeus herbstii. A. Milne Edwards, Cytoplax spinidentata (Benedict), Goniopsis cruentata (Latreille), Aratus pisonii (Milme Eawards), Pachygrapsus gracilis (Saussure), Pachygrapsus transversus Gibbes), Sesarma rectum Randall, Sersama angustipes Dana, Cardisoma guanhunti Latreille, Uca leptodactyia Rathbun, Uca maracoani Latreille), Uca rapax (Smith), Uca panema Coelho, Uca thayeii Rathbun, Uca vocator Herbst), Uca cumulanta Crane, Ocypode quadrata (Fabricius), Ucides cordatus (Linnaeus) e Calappa ocelata Holthuis.

Tagging experiments have been used to study the migratory behaviour of the spiny lobster Panulirus argus (Latreille), off Ceará State, Brazil. An analysis based on vectorial theory has provided the calculation of the coefficient of directional dispersion ( V), the coefficient of randon disperson (a² ) and the centre of density, by quarters of the year. The lobsters were found to engage in breeding migration in the second quarter, when there is a low random dispersion and in feeding migration in the third and fourth quarters, when there is high randon dispersion. The spawning areas are located in offshore regions and the lobsters reach them by moving seawardly, from positions occupied nearer the cost, in the fourth quarter.

The author has reviewed the classification, the nomenclature and the ecological aspects of biologically active compounds, emphasizing the Freyvogel & Perret's (1973) concepts of venomous and poisonous organisms. The literature involving the phyla Annelida, Mollusca and Arthropoda was also reviewed. The author's pharmacological studies performed with the polychaete Eurytlioe camplanata, which revealed a dializable principle, active in the guinea pig's ileum and dorsal muscle ot polvchaete itself are also commented. This principle differs from Acetylcholine and Serotonin. Pharmacologically studies in the sea-hares (genus Aplysia) were also focused, including the author's contribution. In the glands os Aplysia brasiliana, namely the mid-gut-gland, the opaline gland and the purple gland, the author confirmed presence of cholinesters, which are discussed in the review. Toxicity of Arthropods are also discussed, mainly in decapod crustaceans. In some Brazilian crabs studies revealed a pharmacological activity of the gastric secretion expelled with an apparently defensive purpose and its ecological importance is focused in terms of the community. The relatively scarce studies of chemical ecology of marine organisms in Latin America and the importance of these studies were finally emphasized.

Two species of large jelly-fish Aurelia aurita L. and Stomoiophus meleagris Ag, have been registered within a yearly cycle at the system of coastal lagoons "Carmen-Machoria-Redonda ", South of the Gulf of Mexico. A. aurita showed two well defined periods: autumn/winter with predominant young specimens (25 to 100 mm) and spring/summer with a wide adult distribution (200 to 400 mm), beeing the juveniles restricted to the internal, regions of the system. S. meleagris gave evidence of adult populations all year round, the greatest population density occurred during the summer/autumn period with maximum sizes of 200 to 300 mm and during the winter/spring period, juveniles from 10 to 30 mm in December and 50 to 100 mm in April, giving a distribution pattern very similar to A. aurita.

Semimytilus algosus (Gould) 1850, constitutes a potencial resource for cultivation in Chile. The geographic distribution extenas from Manta, Ecuador to the Gulf of Arauco in Chile (Osario & Bahamonde, 1968). Juveniles with a 7 mm mode were collected from the mouth of the Bio-Bio River (36º 48'S, 73º10'W), and were encorded using the Spanish and French systems. These cords, 3 m long, were suspended from an experimental raft (4x4 m) in the western part of Concepción Bay (36º 42'S, 72º 02'W). After 11 months of suspension the mussels had attained a modal lenght of 52 mm, and absolute increase of 45 mm. The maximun length measured was 67 mm. A parallel study of the natural population revealed a slow growth rate, with much smaller maxima than those obtained with the raft. The experimental population seemed to exhibit a short life cycle, as demostrated in part by the rapid growth rate and a high natural death rate before completing a year of suspension. A histological analysis showed S.algosus to be hermafroditic, with mature gametes during the entire year. The gametes varied only slightly in shape and size from the gametes described for other mussel species. Canning tests were made in the local industries. Individuals with a modal length of 36-38 mm yielded 30%, while those of 30 mm individuais used in this experiment, S. algosus demonstrated a yield that compared favorably with that of other comercially important mussels, and would seem to present a great potential for a future induslrial resource.

This is a study of the echinoderms caught during the oceanographic fishery cruise performed by the "B.C. Academic Knipovic"in April, 1973. The recorded specimens are from the South of Chile (45º 08'S; 74º 54'W) and belong to the classes Asteroidea: Ctenodiscus procurator Sladen; Peribolaster folliculatus Sladen; Porania antarctica Smith; Echinoidea: Tripylaster philippi (Gray) and Ophiuroidea: Astrotoma agassizzi Lyman and Gorgonocephalus chilensis (Philippi). New recorded to Peribolaster folliculatus Sladen, 45º08'S; 74º54'W. Ecological data, geographical and batimetric distribution are given.

This study is based essentially on the pattern recognition of concentrations of suspended solids from LANDSAT-2 imagery recorded on CCT's and processed through the IMAGE-100 system. The June 24, 1976 passage over Guanabara Bay and outlying waters was classified using maximum-likelihood and cluster synthesis routines. The thematic map generated by the IMAGE-100 showed high consistency between the distribution of suspended solids and the bi-dimensional models of surface circulation, especially during high and low tides. Biological parameters obtained from the 1977 Environmental Control Program, State of Rio de Janeiro, correlated with orbital data corresponding to the spatial distribution of summer coliform counts. The same could have been deduced for the presence of inorganic dissolved phosphatesin the waters of Guanabara Bay given chemical data.

This paper deal with the length-weight relationship and the condition factor of Macrodon ancylodon caught by trawls along the southern coast of Brazil (29ºS to 32ºS], from September/1976 to August/1977. The total length (cm) was correlated with the weight (g), by means of the expression W = aLb, adjusted by least square method, after a logarithmic transformation. We can observe three periods concerned length-weight relationship: (1) October, November, December and January, with highest weights values; (2) February, March, April and May, with smallest weights values; and (3) June, July, August and September, with intermediary weights between the other periods. We did'nt observe considerable differences between males and females. The condition factor increase with the length increment. The highest condition factor values were observed in November and the smallest in April.

A utilização de sensores remotos em oceanografia tem sido amplamente aumentada principalmente devido aos aspectos sinópticos, ao aumento da precisão das informações bem como do aspecto econômico. Este trabalho apresenta as características e os resultados primários de alguns vôos executados sobre o mar na região próxima a Santos e Ilha de São Sebastião, na costa sudeste do Brasil. A técnica mostrou-se eficiente na verificação dos processos de circulação costeira, bem como em qualquer processo em que se utilize a temperatura como traçador. As correntes de maré parecem exercer grande influência na área próxima a baía de Santos, onde uma velocidade superficial média da ordem de 1,2 m/s foi estimada, e essa influência pode se estender à distância da ordem de 50 mn. Podemos observar também a possível divisão da área, pelo menos superficialmente, em duas sub-áreas, com comportamentos térmicos diferentes, cuja interface se desenvolve normalmente à costa em frente a Santos.

Using a figure which is a combination of volume percentage (Vi) in the axis of x and frequency of occurrence percentage (Fi) in the axis of y it is possible to obtain paralelograms representing the relative importance of the food items. The paralelogram areas are proportional to the volume (%) and frequency of occurrence (%) products; such values are used to calculate a "feeding index" (IAi). This "feeding index'' is proposed as a new method to evaluate the true importance of each food item in the feeding spectrum of each species, as well as to contribute to the understanding of the relationships between several species when applied to fish fauna from the same place and at the same time.

The study of primary production from phytoplankton in estuarine regions is of basic importance, to projects of culture of oysters, shrimps and fishes. In this paper a study was made of the primary production in the Rio Curú's estuary (Ceará-Brasil), during the period from September, 1977 to May, 1978. We used the Winkler's method to make the measurement of productions. The data obtained on oxygen produced varied from 0.03 to 0.04 m LO2 |l| hour of light, for net production and 0.01 to 0.04 ml O2 |l| hour of light for the total production. Qualitative and quantitative studies were also made to obtain the dominant species and the most abundant and most frequent species.