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Distribution and abundance of eggs of Sardinella brasiliensis (=S. aurita), are presented for the years 1970 and 1971 and compared with that of the previous year (1969). The spawning size of three spawning seasons was calculated using Tanaka's method. Incubation time of sardine eggs was estimated using the method of Ahlstrom. During three spawning seasons a considerable change in the relative spawning size was observed. The spawning season (during spring and summer in the southern hemisphere) of 1970-71 was poor when compared with those of 1969-70 and 1971-72. A slight change in the average diameter of eggs in different spawning seasons was also observed. The relation between oceanographie conditions and spawning size was analysed. It is suggested that the warm water covering the spawning ground during the 1970-71 spawning season may have caused an unsuccessful spawning in this year.

Larvae and juveniles of S. brasiliensis (Steindachner, 1879), ranging from 6.4 mm to 35.5 mm, were identified from plankton samples taken in waters off the southern Brazilian coast from 1969 through 1971. Changes in the pattern of pigmentation, body proportions and formation of fin rays are described. During transformation stage a considerable advancement of the dorsal and anal fins was observed. Changes in body proportions are pronounced at the size of 19 mm. Complete ossification of all fin rays is attained at the size of 20 mm, but ossification of the ventral scutes is delayed and completed only at the size of 30 mm. Ossification of the vertebral column was completed at the size of about 16 mm.

O recrutamento do estoque de peixes marinhos é dependente da mortalidade, durante o estágio de ovos e larvas. A corrente de superfície, na área de desova, é um dos fatores importantes que afetam a mortalidade de larvas. O presente trabalho é o resultado de estudos feitos na corrente de superfície por meio de cartões-de-deriva, na região sul do Brasil (entre 22º S e 30º S). Oito viagens oceanográficas foram realizadas com os N/Oc. "Prof. W. Besnard" e "Emília" nos anos de 1969 a 1971. Na região de Ilha Grande, considerada uma das principais áreas de desova, o resultado na época do fim da primavera ao inicio do outono, mostra que os cartões lançados na área este de Long. 44º45' W, derivaram a nordeste e foram encontrados na costa, entre Ilha Grande e Cabo Frio e os cartões lançados na área oeste de Long. 44º45' W, derivaram a sudoeste e chegaram à costa de São Sebastião e Santos. O resultado do cruzeiro de setembro de 1969 (início da primavera) é diferente dos outros. Da região sul de Santos e da região do Cabo de São Tomé, temos poucos dados, portanto, não chegamos a uma conclusão definitiva. Será necessário o estudo contínuo desta área. A maioria dos cartões encontrados foram lançados de estações situadas perto da costa (no máximo, 30 mn). A maioria dos cartões, lançados a uma distância superior, nao foi recuperada.

No presente trabalho são descritas duas novas espécies de isópodes marinhos pertencentes ao gênero Synidotea Harger, 1878, i.e., Synidotea littoralis sp. n. e Synidotea brunnea sp. n.. As espécies foram coletadas nos Estados de Alagoas (S. littoralis sp. n.), Bahia e Espírito Santo (S. brunnea sp. n.), entre algas, na região entre-marés.

This paper deals with the results of drift bottles released in front of the State of Espfrito Santo, off the east coast of Brazil (18º30'S to 20º00'S and 38º40'W to the coast) during the "Rio Doce Project", in July, 1972. Twenty six bottles (10,8%) were recovered out of 240; 52% of those bottles drifted to the south, 40% to the north and 8% directly to the coast. These recoveries may suggest the existence of two branches of the Brazil Current. The coastal one was traced from São Mateus to Ponta de Guriri, with a relatively high velocity of 1 knot. The other branch with a much lower velocity of 1/4 knot is indicated by the observed recoveries up to 27º50'S -48º34'W, 800 nm of their release stations south of the Abrolhos Islands. Hydrodynamic instabilities such as eddies and meanders seem responsible for the retardation of the velocity of the current at the southern part (area of Cabo São Tomé - Cabo Frio). Prevailing south and southeast winds cause the complex pattern of surface circulation in front of São Mateus and Rio Doce.

This paper deals with a study on Brazilian south coast continental shelf demersal fish fauna distribution and Sciaenidae ecology, comprising the latitudes between Torres (29º21'S -49º44'W) and Chuí (33º41'S - 53º27'W). The data on oceanographic as well as on ichthyological variables were obtained from six cruises planned to cover all seasons during the period from April 1968 to March 1969. The variation of the physical conditions of the bottom water layer is studied covering temperature, salinity, dissolved oxygen and type of bottom. The demersal fish families distribution is presented according to its frequencies of occurrence and its particular abundance. As Sciaenidae family shows to be the most important predominant group each species is studied in detail with reference to its distribution and relative abundance, as well as its spatial and temporal variations according to the abiotic environment. Relationship between Sciaenidae species is also discussed concerning feeding habits and the Cole coefficient of inter-specific association is estimated for pairs of species.

O presente estudo constitui-se numa análise preliminar do hábito alimentar do peixe Blennius cristatus Linnaeus, comum nas poças da zona entre-marés do litoral de São Paulo. As coletas foram realizadas na Praia do Poço, Itanhaém (24º12'S -48º47'W), litoral sul do Estado de São Paulo. A poça é rasa e mede 5,0-6,0 m de diâmetro, aproximadamente. O peixe foi capturado com anzol, usando-se, como isca, pedaços de camarão. Os resultados mostraram que B. cristatus utilizou sete ítens alimentares: Alga, Decapoda-Reptantia, Mollusca, Amphipoda, Isopoda, Polychaeta e Bryozoa. Além desses ítens, foram encontrados ainda nos estômagos examinados, areia, muco e fragmentos calcários. B. cristatus mostrou ser uma espécie omnívora, especializada em consumir Hyale media, apesar de, no local de coleta, ocorrerem muitas outras espécies de Gammaridea.

Based on data from two ichthyoplankton surveys carried out off the eastern Brazilian coast in June and November-December 1978, the larval distribution of skipjack is discussed. Skipjack larvae were more abundant in the November-December cruise (southern hemisphere spring). They occurred mainly at stations near the margin of the continental shelf or over seamounts. Out of 240 specimens of scombrid larvae collected in this area, skipjack larvae comprised only 10.4% (25 specimens), whereas the most abundant larvae were Thunnus spp. with 68.8% (165 specimens).

The collection of a specimen of cownose ray in the Colombian Caribbean is reported. Based on the presence of 9 rows of teeth in both jaws, it was identified as Rhinoptera Müller & Renie. The range of the species is extended 7,300 km, from Rio de Janeiro to Isla de Salamanca. Some comments on the size at birth and habits of the species are made.

Foram determinadas as velocidades de crescimento e de assimilaçao da diatomácea Phaeodactylum tricornutum, em função da concentração de nitrato e amônia. A fluorescência "in vivo" da cultura foi comparada com o número de células nas culturas crescendo em diferentes concentrações de nitrato e amônia. A velocidade de crescimento foi determinada como clorofila-a sintetizada, número de células no meio de cultura e assimilação de carbono durante a fotossíntese. A velocidade de assimilação de nutrientes foi determinada como nitrato e amônia consumidos. Foi observada inibição na velocidade de assimilação do carbono inorgânico, com a adição de nitrato ao meio de cultura.

Seasonal changes in phytoplankton populations in the chlorophyll-a concentration and on some environmental factors were studied monthly from June 1974 to September 1975 at Ubatuba, northern coast of São Paulo. Water temperatures ranged from 20ºC in August to 29.5ºC in March and salinities from 33.06 º/.. in March to 35.80 º/.. in January. The maximum salinity value observed in January near the bottom, associated with the thermal stratification found only during this month, seems to indicate an oceanic contribution to the enrichment of the local water mass. Pluviometric values ranged from 37.2 mm in August to 468.5 mm in January. Phytoplankton cell counts fluctuated from 64,000 to 1,028,000 cells/l and chlorophyll-a values varied from 0.52 to 6.86 µg/l. Maximum standing-stock was observed during summer, particularly in March, and it is probably associated with land drainage due to precipitation. A second bloom was observed in September 1975, and it is associated probably with the discontinuous impact of the wind. The phytoplankton populations were dominated by unidentified phytoflagellates, followed by diatoms and dinoflagellates. Nitzchia closterium and Thalassionema nitzschioides, along with Navicula sp., were the most representative species of diatoms. Among the dinoflagellates, Gymnodinium sp. was the most important. Blue-green algae and silicoflagellates were poorly represented. The diatoms Chaetoceros simplex, Chaetoceros spp, Nitzchia longissima, Nitzchia spp, Rhizosolenia delicatula and Rhizosolenia stolterfothi were found with high densities, only during bloom periods. The chlorophyll-a fractionation experiments demonstrated that organisms in size classe smaller than 20 µm represented, for all depths, between 54.93 and 98.15 º/.. of the total phytoplankton population.

The present work deals with twelve species of Sphaeromatidae from several substrata in the intertidal and shallow infralittoral zone in São Paulo and Rio de Janeiro States, Brazil. Sand, stones, empty tests of barnacles, empty tubes of polychaete, byssus of mussels, oyster beds, macroscopic algae and sea grass (Spartina alterniflora) were collected and analysed. The following nomenclatural changes have been made: Pseudosphaeroma jakobii and Exosphaeroma platense are synonymyzed with Cassidinidea tuberculata; Pseudosphaeroma rhombofrontalis is placed in the genus Tholozodium; Paradynoides brasiliensis antonii with D. tropica. A key to species, the geographical distribution and notes on the habitat of the species are also furnished.

A total of 4751 pairs of otoliths of Sardinella brasiliensis was colected between 22ºlat S and 28º lat S along and offshore the Brazilian coast. These pairs were studied to ascertain whether otoliths can be used as a reliable character for the assessment of individual age and population characteristics. The morphology of the otoliths is discussed in detail. Both periodic and non periodic rings (Tr and TPN) are shown to occur. TR and TPN are related to events during the larval and juvenile stages. Well defined growth rings are also present and may be used as age indicators. Morphologic and morphometric characters, specially length of rostrum, lenght of anti-rostrum and weight are correlated with total length; the results confirm earlier studies by different methods that suggest that the species, in the region studied, is broken down into different groups imperfectly isolated from one another. In conclusion, the study of details of the otoliths of this species is an useful addition to others as a mean to separate the various groups. Spatial and temporal distribution of specimens with different types of otoliths suggeets a certain degree of mixture among groups through migration of individuals and partial overlapping in space.

Otoliths can be used as a reliable character for the assessment of individual age of S. brasiliensis from Brazilian coast (22ºS - 28ºS). Well defined growth rings are present and may be used as age indicators. The otolith growth parameters would seem to indicate that there are four distinct patterns along the areay suggesting that the species, in the region studied, is divided into distinct groups.

Phytoplankton primary production and the maximum photo synthetic index (Pb m) from the region of Bay of Santos were measured every two months during 1976 by simulated incubations using 14C method and incandescent lamps (737 µE.m-2 .s-1;40 klux) . The results obtained for production rates (maximum of 204.6 mgC.m-3.hr-1 in winter and 488.3 mgC m-3.hr-1 in summer) are among the highest recorded for tropical marine environments. A high capability of light adaptation under high temperatures was also verified. The photo synthetic indexes obtained were also very high and seems to be due to the high nutrient level of the region. The eutrophic state is supported by the high nutrient and chlorophyll-a concentrations and by the phytoplankton cells number.

The highest level of detergents was obtained in the interior of the Santos Channely in front of Channel 6 and also in the vicinity of the Santos ocean outfall diffusor. There are thus three principal soucers of detergents in this region: a. the Cubatão industrial complex, and the Billings reservoir; b. the city of Santos (unauthorized sewage connections); c. the ocean outfall. Detergent levels obtained vary between 0.11 and 0.97 ppm ABS.

It is shown how to get rid of iterative process to compute wavelengths and haw the celerities and their derivatives can be computed in terms of wavelengths for any depth, without using hyperbolic functions.

The seasonal and spacial distributions of dissolved oxygen, temperature and salinity of surface and bottom waters over the continental shelf south of Torres, southern Brazil, were investigated from April 1968 to March 1969. The maxima and minima values of oxygen concentration in the upper layers were observed during the winter and summer along the coast (10-35 nm), respectively. Near the bottom this characteristics changes reflecting the northward advection of low oxygen water along the coast. For the sections along the continental shelf covering distances up to 100 nautical miles, the association of high oxygen concentration with low temperatures and low oxygen concentration with higher temperatures was also observed for distances no longer than 60 ran. Further east and below the surface layer, this tendency is modified by the advection of oceanic water from tropical and subantarctic origin. Near the coast, the oxygen maxima (5.0 ml/l) is associated with salinity values ranging from 30 to 33‰ (temperature values between 12 and 15ºC), indicating that (its occurrence) is probably due to the fresh water run-off from La Plata River. Some results of the changes in the nutrient concentrations during 1972 are also described.

Seasonal differences in sigma-t (1.8)3 temperature (4.0ºC) and salinity (0.9‰) were observed during February/June 1976 in the vicinity of Ilha Grande off the coast of Brazil Estimates of static and dynamic stability were made through the calculation of Brunt-Vaisala frequencies and Richardson numbers, respectively. Both static and dynamic stability values were larger in February than in June for the same location and suggest a greater column stability in February than in June. Stations located in the northern and western channels of Ilha Grande, however, contained greater density reversals than to the east of the Island. Small scale dispersion studies were made using Rhomamine B dye to determine horizontal diffusion coefficients (K) east of the Island and in an embayment of the Island. The estimate for K was 9X10³ cm² s-1 east of the Island, about 2.6 times greater than the value estimated for the protected embayment.

Measurements of excreted dissolved organic matter (DOM) were carried out twice (in simmer and winter) using natural phytoplankton populations from "Enseada do Flamengo" (Lot. 23° 30'S-Long. 045°069'W) and enriched artificially with nutrients. The bioassays were carried out inoculating samples of an integral sea water in ten liters flasks, incubated "in situ". Measures were taken in populations growing in: integral " f " media, "f" - N, "f" - P, "f" - (H + P), "f" - (Vit. + Metal traces), and in a control without enrichment. The absolute amount of excreted DOM generally followed the quantity of total carbon assimilated. In the meantime, with the populations with nitrogen deficiency occurred an increase of relatives rates of excretion, not only due to the total carbon assimilation diminution, but effectively also to the absolute increase of the quantity of excreted DOM.