Green mud differs to a greater extent from the blue mud, and owes its characteristic nature and colour to the presence of glauconite, which is formed inside the cases of foraminifera, the spines of echini and the spicules of sponges in a manner not yet understood. [Please select]
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” On embryological grounds, he observes, we should “place true Echini lowest, then the Clypeastroids, next the Echinolamps, and finally the Spatangoids. [Please select]
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Its proper diet consists of the smaller marine animals, such as crabs, echini, and molluscs, alive or dead, fish and carrion. [Please select]
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