ABSTRACT: Eocene rocks of theWaseiyit Formation are exposed at Gebel Hammam Faraun, on the eastern coast of the Gulf of Suez in west central Sinai (Egypt). The formation represents gravity flow sediments deposited in response to early Eocene tectonic activity. Three species of the genus Nummulites were encountered in this formation: Nummulites burdigalensis de la Harpe 1926, Nummulites alpinus Schaub 1951 and Ruetimeyerina murchisoni (RÃ¼timeyer 1850) n.gen. The three species assign the Waseiyit Formation to the Early Eocene, at the base of the Late Ypresian (shallow benthic zone SBZ 10). These findings show that granulated Nummulites such as N. burdigalensis first occurred at the base of the Late Ypresian, just after the appearance of non-granulated Nummulites in the earliest Ypresian. The Nummulites assemblage recorded by Boukhary et al. (1998) differs from assemblages previously collected from the Monastery of St. Paul area (Eastern Desert, Egypt). The St. Paul assemblage contains Nummulites praeatacicus, Nummulites sahariensis and Bassiounina sanctipauli and is therefore older than the material recorded by Boukhary et.al. (1998) from theWaseiyit Formation. Biotic differences between the two sites suggest that specific faunal elements are indicative for early and late Ypresian deposits.