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Deep Sea Drilling Project Hole 534A of Leg 76 was drilled in the Blake-Bahama Basin about 500 km east of Florida (28°20.6'N, 75°22.9'W). It is situated east of the Blake Plateau escarpment and north of Hole 391C (28°13.61'N, 75°37.OO'W), which also furnished remains of cephalopods. The purpose of drilling at Hole 534A was to reach the oceanic basement and to investigate the oldest sediment overlying it, thought to have been deposited in the Middle Jurassic. The main objective of the present study is to increase our knowledge about the correlation of ammonites and aptychi in the Lower Cretaceous of Hole 534A. This knowledge can improve our delineation of stage boundaries. Between 980 and 1380 m sub-bottom (i.e., between Cores 51 and 96), 21 core samples with macrofossils were recovered. The range in age of the fossils examined reaches from latest Tithonian (Core 96) to late Barremian (Core 51). The interval between Cores 51 and 92 is within the Blake-Bahama Formation. Its lithology consists predominantly of pelagic laminated marls, calcareous siltstones, and claystones showing light gray to whitish shades. The sediment below Core 92 is composed of calcareous claystones characterized by reddish brown colors. The interval between Cores 92 and 96 represents the upper part of the Cat Gap Formation. The contact between the Blake-Bahama Formation and the Cat Gap Formation is placed at Core 92. (See Site 534 report, this volume). Determinable macrofossils are present in 19 of the 21 samples available. All belong to the Class Cephalopoda Cuvier, 1797. The order Ammonoidea is represented by four ammonites and 15 Lamellaptychi. Three ammonites belong to the Ammonitina Hyatt, 1889, and only one belongs to the Lytoceratina Hyatt, 1889. Decapoda are represented by one specimen of the Family Belemnitidae d'Orbigny, 1845. A small rhyncholite has been isolated by F. M. Gradstein from Core 94. The ammonites permit the recognition of upper Barremian (Pulchellia), the probably upper Valanginian (IPaquiericeras), and the Valanginian in general (Neocomites). Lamellaptychi are distributed all over the section examined. The oldest aptychus available is from Core 96. It represents a Lamellaptychus beyrichi (Plate 1, Fig. 19), which is a form that characteristically indi-

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Early Cretaceous Cephalopoda from the Blake-Bahama Basin (Deep Sea Drilling Project Leg 76, Hole 534A) and Their Correlation in the Atlantic and Southwestern Tethys