The series between the marine Callovian and marine Aptian is divisible into a lower and an upper group. The lower group is predominantly limestones, marls or clays, and rare sandstone. Fossils collected from the unit suggest lacustrine or brackish water deposition of the Purbeckian. Sediments of the upper group--sandy shales unconformable on the lower group--originated from the neighboring continental surfaces. Since only fossil imprints were found, the group is dated as Wealden on the basis of the underlying and overlying units. Calcareous sponges and limestone facies with bryozoans and sponges are illustrated and briefly described from the localities studied. Iberina lusitanica (foraminifera) and Dictyocythere aff. mediostricta (ostracode) are described and figured.