Abstract
DOURING our southern cruise the sounding-lead brought up five absolutely distinct kinds of sea-bottom, without taking into account the rock and detritus of shallow soundings in the neighbourhood of land. Our first two soundings in 98 and 150 fathoms on the 17th and 18th of December were in the region of the Agulhas current. These soundings would have been naturally logged “greenish sand,” but on examining the sandy particles with the microscope, they were found to consist almost without exception of the costs of foraminifera in one of the complex silicates of alumina, iron, and potash, probably some form of glauconilc. The genera principally represented by these casts were Miliola, Biloculina, Uvigerina, Planorbulina, Rotalia, Textularia, Bulimina, and Nummulina; Globigerina, Orbulina, and Pulvimiiina were present, but not nearly in so great abundance. There were very few foraminifera on the surface of the sea at the time. This kind of bottom has been met with once or twice before; but it is evidently exceptional, depending upon some peculiar local conditions.
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THE “CHALLENGER” EXPEDITION * . Nature 11, 95–97 (1874). https://doi.org/10.1038/011095a0
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DOI: https://doi.org/10.1038/011095a0