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From the documentation of the Neogene planktonic foraminifer species from 126 samples of DSDP Leg 40 Sites 360 and 362 in the southeastern Atlantic, a comparison is made of the two sets of faunas within the framework of the established Austral biostratigraphic zonal scheme. A species diversity difference exists between the two sites with a greater species number at Site 362 due to the migration southwards of exotic species which did not reach Site 360. A strong affinity exists between the faunas of Sites 360 and 362 and those of southeastern Australia and New Zealand, probably due to their similar latitudinal positions and to the circum-Antarctic current connection. INTRODUCTION For the convenience of this Neogene report on the planktonic foraminifer faunas of Sites 360 and 362 in the southeastern Atlantic (Figure 1), the base of the Miocene is taken at the initial appearance of Globorotalia kugleri Bolli and the upper Miocene boundary at the initial appearance of Globorotalia margaritae Bolli and Bermudez. Both sites yielded excellent faunas, and species from the southern Site 360 (lat 3O°51'S, long 18°O5'E) have been recorded from the lower Miocene Globigerina woodi connecta Zone through the lower Pliocene Globorotalia puncticulata Zone (Table 1). Similarly, species from the more northern Site 362 (lat 19°45'S; long 10°32'E) have been recorded from selected samples from the lower Miocene Globoquadrina dehiscens Zone through to the upper Pleistocene to Recent Globorotalia truncatulinoides Zone (Table 2). Thus it is possible to make a direct comparison of the faunas of the two sites for the whole of the Miocene and basal Pliocene, and use this information to elucidate the oceanic conditions in the southeastern Atlantic at this time. A complication is that solution effects at both sites have effectively reduced species diversity in some individual samples. Significant faunal differences existed between the two sites throughout the Miocene, mainly because of the higher species diversity at the more northern Site 362; only a few species existed at Site 360, apparently restricted to the relatively cooler southern waters (for example, Globorotalia zealandica Hornibrook in the lower Miocene Globigerinoides trilobus trilobus Zone). Even so, the fauna from Site 362 was never entirely tropical in the Neogene, not only because of the lack of certain species (e.g., Globorotalia fohsi robusta Bolli, Pulleniatina obliquiloculata [Parker and Jones], Globigerinoides ßstulosus [Schubert], etc.) but also more 30° W 0" 30° E Figure 1. DSDP Leg 40 Sites 360 and 362. significantly because of the paucity of certain tropical species even when present (e.g., Globigerinatella insueta Cushman and Stainforth, Sphaeroidinella dehiscens [Parker and Jones], and Globoquadrina tripartita [Koch]). Also, the dominant keeled Globorotalia in the middle-upper Miocene was the cooler water Globorotalia miozea Finlay and thereafter in the PliocenePleistocene, keeled Globorotalia are generally absent except for small Globorotalia menardii (d'Orbigny) which was restricted to only the lower part of the Pliocene Globorotalia puncticulata Zone. This interpretation of a progressive cooling is supported by the lack of known tropical species such as Globorotalia 723

Neogene Planktonic Foraminifers from DSDP Leg 40 Sites 360 and 362 in the Southeastern Atlantic