ABSTRACT
The Coralline Crag, probably the oldest deposit, contains corals of the warm Astian seas, animals that today would face certain death in the cold waters of the North Sea. In later deposits the corals vanish, to be replaced by shells of molluscs now inhabiting the northern seas. The Crags are overlain by the Forest Bed Series, a sequence of interglacial deposits with a very rich fossil fauna and flora. There are two distinct interglacials with individual floral sequences, separated by a cold oscillation. The fauna of the older interglacial is particularly well represented in the neighbourhood of Bacton on the eastern coast, while the younger fauna may be studied at Cromer further to the north. In both cases the faunas are of a temperate forest type. Compared to the Villafranchian faunas, the Forest Bed assemblage is markedly rejuvenated: now, for the first time, modern species in appreciable numbers turn up.
