INOCERAMID LARVAL PLANKTOTROPHY - EVIDENCE FROM THE GAULT FORMATION (MIDDLE AND BASAL UPPER ALBIAN), FOLKESTONE, KENT

It has long been postulated that inoceramid bivalves had a long-lived planktotrophic larval stage because of their cosmopolitan distribution in the Cretaceous. This is now proven by the discovery of large larva l shells preserved on inoceramid adult umbones from the Gault Formatio n at Folkestone. The developmental structure of these larval shells in dicates that they were planktotrophic, living in the water column for in excess of 50 days. However, neither the inoceramid larval shell sha pe nor the hinge structure throw any new light on the taxonomic affini ties of this extinct bivalve family.