This research will examine the biostratigraphy and extinction patterns of ammonites, inoceramid bivalves, and echinoids at well-preserved stratigraphic sections of Maastrichtian age located in Spain and France. Specimens will be collected stratigraphically. Bulk samples to be processed for microfossils will also be collected. The results of these collections will allow testing of hypotheses concerning the timing and pattern of macrofossil extinctions in these sections. A refined biostratigraphy will also be proposed, by integrating information from new macrofossil occurrences. Inoceramus (Bivalvia) shell prisms will also be collected from ODP core samples to test the hypothesis that these Cretaceous bivalves became extinct prior to the ammonites in the world's oceans.