British Cretaceous Echinoids

Abstract

Part 6 continues the description of the irregular echinoids from the British Cretaceous, dealing exclusively with the cassiduloid genera. Cassiduloids are restricted to the more inshore, sandy facies in the British Cretaceous and are thus absent above the Cenomanian when chalk facies predominate. Sixteen species, belonging to eleven genera are described. One new species, Ochetus pauli, is described, and the new subfamily Stigmatopyginae is proposed. Three genera, Clypeopygus, Pygopistes and Penesticta, represent new records for the British Cretaceous.