Late Neogene planktonic foraminiferal and calcareous nannofossil biostratigraphy of the Upper Coastal Group on the island of Jamaica is compared with the planktonic succession in the Gulf of Mexico and with the standard European stages and reference sections in Italy. Correlation of epoch boundaries and other paleontologic data from the Italian to the Caribbean and Gulf of Mexico regions utilizes restricted occurrences of planktonic foraminiferal and calcareous nannofossil species common to both regions. Species important for this intercontinental correlation and dating include: Globorotalia acostaensis, Sphaeroidinellopsis sphaeroides, Discoaster challengeri, and D. extensus in late Miocene; early Pliocene Globorotalia margaritae and Discoaster quinqueramus; middle and l te Pliocene species of the Globorotalia crassaformis lineage, Sphenolithus abies, and Reticulofenestra pseudoumbilica; and appearance of Globorotalia truncatulinoides, Helicopontosphaera sp., and Gephyrocapsa oceanica, and faunal evidence for onset of climatic deterioration in early Pleistocene.

Climatic criteria obtained by analyses of the planktonic fauna provide a basis for recognition of the Pliocene-Pleistocene boundary within the most continuous and fossiliferous exposures of late Neogene marine sediments in the Gulf of Mexico and Caribbean region. On the basis of these data a sequence of planktonic foraminiferal zones and subzones is compared with the polarity reversal stratigraphy within the Gilbert, Gauss, and Matuyama geomagnetic epochs.

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