Jukes-Browne & Hill (1903, 1904) - Marsupites Zone
Biostratigraphical correlation: It is inferred that Jukes-Browne & Hill (1904) largely followed Rowe (1900) in the definition of this zone. It therefore equates with the U. socialis Zone, M. testudinarius Zone, U. anglicus Zone and basal O. pilula Zone of current usage (Young & Lake, 1988).
Lithostratigraphical correlation: Equates with the lower part of the Newhaven Chalk Formation of southern England.
Age: Late Santonian & Early Campanian.