INTERGLACIAL EPOCHS. 263 



cold, supporting only a meagre arctic flora. Eventually an 

 extensive ice-sheet overflowed the land, and crept south into 

 Norfolk and probably even into Suffolk. 



The Cromer boulder-clay and its associated deposits of loam, 

 sand, and gravel, with large erratics, are overlaid by certain 

 gravel-beds, which are believed to be the continuation of a series 

 of sand- and gravel-deposits somewhat widely spread over East 

 Anglia. These are usually supposed to be exclusively marine, 

 and they have yielded marine shells which, according to Mr. 

 S. V. Wood, have a preponderating southern facies. Here and 

 there, however, as near Ipswich, they are associated with beds of 

 brick-clay, which seemed to me to be of freshwater origin, and 

 in which fragments of wood, sticks, and logs, have been found. 

 Similar brick-earths occur in the neighbourhood of Brandon, 

 Suffolk, where they have yielded to the researches of Mr. 

 Skertchly implements of characteristic Palaeolithic types, along 

 with freshwater-shells and fragments of bones. This is by far 

 the most important discovery of Palaeolithic beds which has 

 been made since Boucher de Perthes first detected the flint im- 

 plements in the ancient river-drifts of Abbeville. And it is 

 more especially gratifying to me as it confirms by direct evidence 

 the views I had been previously led to form as to the inter- 

 glacial age of many of the implement-bearing deposits of England. 



Thus we have evidence to show that after the ice-sheet 

 which laid down the Cromer till had melted away mild con- 

 ditions of climate ensued. The sea, which then covered some of 

 the low ground of East Anglia, gradually became tenanted with 

 a group of shells which indicate plainly a temperature not lower 

 than that of the seas which now wash the English coast. More- 

 over, the Brandon freshwater loams and brick-earths show that 

 Palaeolithic man had now become a resident in England, and 

 doubtless he would be accompanied by many of the Pleistocene 

 mammals which had been driven south on the approach of the 

 preceding glacial epoch. 



Overlying the Brandon beds, with their flint implements, 

 comes the great chalky boulder-clay, or bottom-moraine of an 



