07 August 1998
Vol 281, Issue 5378

About The Cover

Cover image expansion

COVER Coarse residue from a Miocene limestone of New Zealand consists of skeletal fragments of cheilostomes and cyclostomes, two bryozoan groups that responded differently to the Cretaceous-Tertiary extinction. The diversity of both groups was reduced by the extinction, but while cheilostomes remained relatively more diverse, the cyclostomes became more abundant for several million years. See page 807. [Photograph: H. Taylor]