"Study of planktonic foraminifera from an equatorial Pacific core dated by Hough and Urry as Pleistocene reveals typical modern warm-water species from top to bottom. . . . It is believed that tests on the bottom truly reflect surface-water temperatures. Modern planktonic foraminifera date mostly from the pre-Pleistocene, and thus lived through the ice ages, but warm-water forms were restricted to areas near the equator during these times. The evidence tends to support Arrhenius' conclusions that there is little calcium carbonate accumulation at present, that the maximum accumulation occurred during the ice ages, and that the same warm-water faunas lived continuously near the equator throughout the Pleistocene."