• Volume 46, Issue 5

      November 1957,   pages  293-345

    • Thermal field and oceanic circulation along the east coast of India

      A A Ramasastry C Balaramamurty

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      From the bathythermographic data, collected during the first 19 cruises of the Andhra University during the period October 1952 to April 1953 along the east coast of India, thermal fields at surface, 40, 100, 200 and 400 feet levels have been constructed for the three seasons,viz., Post-Monsoon, Winter and Summer seasons. The present study is confined to the coastal region between latitudes 13° N. to 18° N. and longitudes 80° E. to 84° E. In addition to this area, during winter season, the study has been extended to an area over theSwatch of No Ground. From the above, circulation has been deduced and the current directions have been entered on the charts. The limitations and the validity of the method in entering the current directions is discussed and further it is shown, from a consideration of the current boundaries, that the method yields a fairly good representation of the oceanic circulation at various depths. Seasonal variation in the thermal structure and the associated circulation is presented.

      In the Post-Monsoon and Hot Weather seasons the current pattern indicates turbulence in the surface layers as a consequence of sinking and upwelling. Greater turbulence occurs off Visakhapatnam than off Madras. At a level at which thermocline forms, currents are opposing to those found above and below that level. A nearly isothermal water mass which forms over the continental shelf during the Hot Weather season appears as a semi-permanent feature, keeping its position due to the existing north-easterly current.

    • Hyphomycetes—IV

      C V Subramanian

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      The following five new species of Hyphomycetes, collected from the Nilgiris, Madras State, are described in this paper:Arthrobotryum nilgirense on dead bamboo,Ceratosporella deviata on dead leaf base ofRaphilostyles sapida, Periconia nilagirica on dead culms of grass,Stachybotrys nilagirica on dead twigs ofAlthœa rosea, andDrumopama girisa on dead leaves of Gramineæ. Of these,D. girisa is proposed as a gen. et sp. nov. and is placed in the Moniliales-Phæostilbeæ-Amerosporæ.Harpographium fasciculatum Sacc. is recorded from India for the first time.

    • Tænioma J. Ag. from India

      T V Desikachary M S Balakrishnan

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      Both the known species ofTœnioma, T. perpusillum J. Ag. andT. nanum (Kuetz.) Papenfuss, are here reported for the first time from India. General features of thallus organisation in both species are described in detail. The development of tetrasporangia in T.Perpusillum is described. In general, the writers’ observations are in agreement with those of Papenfuss. The taxonomy of the genus is discussed and the authors agree with Papenfuss in keeping the two species distinct.

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