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The analysis of 104 core-catcher samples from Site 603 resulted in a continuous palynological record from the middle Miocene to early Pleistocene. Two palynological zones could be established (Zone 2, below 380 m: high Pinus, Quercus, and Carya values; Zone 1, above 380 m: high Pinus, and Sphagnum values). The marine pollen record was found to reflect the history of the vegetation of the eastern United States, the flora from Zone 2 indicating a warmer climate than that from Zone 1, which depicts a climatic cooling trend. The onset of Western Boundary Undercurrent deposition had no noticeable effect on the pollen distribution in the marine sediments. INTRODUCTION DSDP Site 603 is located on the lower continental rise 435 km east-southeast of Cape Hatteras (Fig. 1). Palynomorphs were examined from 54, 12, and 38 corecatcher samples from rotary-cored Holes 603 and 603 B, and HPC Hole 603C, respectively. The purpose of this preliminary study was to determine the character (qualitative/quantitative) of the palynological contents of the sediments, its potential for biostratigraphy below the CCD, its relation with the onshore vegetation and climate, and the influence of the Western Boundary Undercurrent on the pollen distribution in the sediments. METHODS We prepared 10 cm samples from the available core-catcher material using the following standard technique. HC1, Na-pyrophosphate, acetolysis treatment; bromoform separation (2 ×) , and sieving over a 7 μm nylon mesh. Slides were mounted with glycerol jelly, and the cover-slips were sealed with paraffin. Mesozoic and Paleogene forms (Aquilapollenites, Classopollis, Trudopollis, etc.) could be identified as reworked. No attempt was made to recognize reworked late Cenozoic pollen, because the use of autofluoresence as described by Gijzel (1967) would be too time-consuming, and staining techniques (Stanley, 1966) do not discriminate reworked from nonreworked Neogene pollen. The standard pollen count is + 200 angiosperm and gymnosperm pollen. Percentages of all the palynomorphs are calculated on that standard pollen sum. Most trilete spores, monolete spores, fungi spores, microforaminifers, dinoflagellates/acritarchs, and denticles were grouped and not further differentiated. RELATED STUDIES Modern Marine Palynology Studies of marine sediments include work by Heusser (1983) on the pollen distribution in surficial sediments from the slope and rise of the western North Atlantic, and by Stanley (1966) on the Palynology of Quaternary 1 van Hinte, J. E., Wise, S. W., Jr., et al., Init. Repts. DSDP, 93: Washington (U.S. Govt. Printing Office). 2 Present address: Palynological Department, Hugo de Vries Laboratory, University of Amsterdam, 1018 BX Amsterdam, The Netherlands. sediments from the continental shelf and ocean basin of the northwestern Atlantic. These sediments off the eastern coast of the United States contain high values of Pinus (pine) pollen (up to 90%), with less Quercus (oak) (10-20%) and other pollen types in very small numbers only. In general, the Palynology of the marine sediments is a reflection of the vegetation of the adjacent land area, with a seaward increase in the relative frequency of Pinus pollen, and a seaward decrease in variety of pollen types. Recent Onshore Pollen Distribution According to Davis and Webb (1975), the southeastern North American forests are characterized by high percentages of Pinus (30-70%), Quercus (15-30%) and southeastern tree pollen: Taxodium (cypress), Liquidambar (sweet gum), Nyssa (black gum), and Liriodendron (tulip tree) (5-45%). Other common species are Carya (hickory), Betula (birch), and Ulmus (elm) (up to 5%). Locally important are, amongst others, Acer (maple), Alnus (alder), Corylus (hazel), and Juglans (walnut). Late Tertiary Floras Palynological studies by Traverse (1955) on the Brandon lignite, Vermont (upper Oligocene or lower Miocene), and by Rachele (1976) on the Legler lignite, New Jersey, give some information on the late Tertiary vegetation of the eastern United States. Apart from local swamp elements, one of the numerically important species is Quercus (mostly 30-70%); Pinus occurs in larger numbers only in the Legler lignite (up to 20%). The dominant vegetation of the Brandon lignite, excluding the swamp elements, contains Quercus, Engelhardtia, Carya, and Ulmaceae, that of the Legler lignite is Quercus, Pinus, and Carya. RESULTS From the 104 samples analyzed, three (603B-14,CC, 603B-15,CC, and 603B-16,CC) proved to be barren of palynomorphs. Two samples (603-10,CC, and 603-15,CC) contained less than the standard + 200 pollen count, but

Neogene Palynology of Deep Sea Drilling Project Site 603 on the Lower Continental Rise, Northwestern Atlantic