THE AMCEBAS 



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bigerinida, and, to a small extent, to the remains of minute pelagic algae, known as 

 coccospheres and rhabdo spheres; the broken fragments of the latter in the shape of 

 discs and rods being termed coccoliths and rhabdoliths. Over the greater part of 

 the floor of the Atlantic, and over immense tracts in the Western Indian Ocean and 



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Polystomella (magnified 200 diameters). 



