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Sediment samples have been collected from the Schirmacher Oasis and adjoining area in East Antarctica; these areas consist of polar ice, ice-free area, lakes and the coastal shelf area. The 37 samples have been analysed for their grain-size parameters and statistical relationships. The oasis is characterised by ongoing glacial processes, including deposition and erosion of the sediments by ice, meltwater and winds, thus influencing the sediments in various ways. Basic statistical grain-size parameters like graphic mean, standard deviation, skewness and kurtosis have been calculated for the four units. The sediments of all areas are almost all poorly to very poorly sorted, fine-skewed to near-symmetrical and platykurtic to leptokurtic in nature. Bivariate plots between the grain-size parameters have been interpreted. They do, apart from a few exceptions, not show any trend suggesting relationships between the sediments of the four landscape types. Both t-and F-tests have been applied on the samples, and the phi values and grain-size parameters have been analysed; these show that the group variances of the samples are not significant, but that the phi-values are significant.

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There are various opinions as to what parameter influences the coiling directions in foraminifera. "Do microspheric and megalospheric generations have different coiling ratios?" is an unanswered question in foraminiferal studies. Per view of this, an attempt is made to study the relationship between mode of reproduction (sexual/asexual) and coiling direction (dextral/sinistral) in the benthic foraminiferal species Rotalidium annectens (Parker & Jones). Proloculus (initial chamber) size is taken as an indicator of changes in reproductive behaviour.The present study is based on the observations made on 17722 specimens of this species from 186 samples, obtained from 3 sediment cores (representing a time span of about 9,500 years) from the shallow water region off Kanvar, west coast of India. The results indicate an inverse relationship between mean proloculus size and dextrality (YO of dextral forms) which is statistically confirmed. The correlation value (r = -0.57) between the two parameters is above the level of significance at 99% level. Therefore, it is inferred that microspheric generation (smaller proloculus) prefers dextral coiling and coiling in benthic foraminifera appears to be influenced by mode of reproduction. J. Micropalaeontol., 11 (2), 221-228, December 1992. INTRODUCTIONInnature many organisms suchas gastropods, bacterial colonies (Bacillus rnycoides), the spiral vascular conductors of some plants and the spiral distribution of leaves, show differences in coiling direction. Many trochospiral foraminiferal species possess asymmetric tests in which chambers are arranged in a cone-like spiral. This spiral may coil either in an anti-clockwise, sinistral (left handed) or in a clockwise, dextral (right handed) direction.These changes in coiling direction are the most commonly studied morphological variable exhibited by foraminifera (reviews by Scott,

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. The Micropaleontology Project, Inc. is collaborating with JSTOR to digitize, preserve and extend access to Micropaleontology.ABSTRACT: From the shallow region off the central west coast of India, 21 samples of surface sediments (ranging in depth from 22 to 52m) along with two sediment cores of 4.80m and 4.00m (surface/subsurface) have been analyzed for foraminiferal composition and diversity. A total of 177 species have been identified and illustrated by scanning electron photo micrographs. Seventy-two genera, 47 families, 26 super families and 5 sub orders are represented. In order to have insight into paleoclimatic changes in this region, quantitative spatial distribution data was generated for morpho-groups (angular-asymmetrical and rounded-symmetrical). The distribution revealed less abundance of angular-asymmetrical forms at the river mouth thus indicating an inverse relationship of angular-asymmetrical morpho-groups with river discharge (low salinity water). The reverse is true for rounded-symmetrical forms. The down core profiles of these parameters revealed major wet periods at around 3200 years BP and 1000 AD separated by a dry spell at around 2000 years BP. Our inference is in agreement with the climatic conditions reported elsewhere in the world. PLATE 2 11 Quinqueloculina seminulum (Linne') X155; a; 4 chambers view; b; apertural view; c; 3 chambers view (GOD NIO Cat. No. K-43) 12 Quinqueloculina seminulum (Linne'); a, 4 chambers view X150; b, apertural view X150; c, enlarged aperture X590 (GOD NIO Cat. No. K-43) 13 Quinqueloculina schlumbergeri (Weisner) X150; a, 4 chambers view; b, 3 chambers view (GOD NIO Cat. No. K-42) 14 Quinqueloculina tropicalis Cushman X160; a, 4 chambers view; b, 3 chambers view (GOD NIO Cat. No. K-44) 15 Quinqueloculina undulose costata Terquem X195; a, 4 chambers view; b, 3 chambers view (GOD NIO Cat. No. K-45) 16 Quinqueloculin venusta Karrer; a, 4 chambers view X135; b, apertural view X140; c, 3 chambers view X135 (GOD NIO Cat. No. K-46) 17 Quinqueloculina vulgaris d'Orbigny; a, 4 chambers view X125; b, apertural view X140; c, 3 chambers view X125 (GOD NIO Cat. No. K-47) 18 Quinqueloculina sp. X135 (GOD NIO Cat. No. K-48) 19 20 Quinqueloculina sp. X140 (GOD NIO Cat. No. K-48) Quinqueloculina sp. X135 (GOD NIO Cat. No. K-48) 21 Miliolinella australis (Parr) X125, 4 chambers view, (GOD NIO Cat. No. K-49) 10 Triloculina sp. X190 (GOD NIO Cat. No. K-57) 11 12 Borelis sp. X30 (GOD NIO Cat. No. K-58) Dentalina communis d'Orbigny X160 (GOD NIO Cat. No. K-59) 13 Nodosaria catesbyi d'Orbigny X160 (GOD NIO Cat. No. K-60) 14 Nodosaria sp. A X170 (GOD NIO Cat. No. K-61) 15 Nodosaria sp. B X150 (GOD NIO Cat. No. K-62) 16 Lenticulina macrodiscus Cushman...

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