INTRODUCTION Since the publication of Dr. J. G. Andersson’s important “Essays onthe Cenozoic of Northern China” in 1923 much material has accumulated, partlyas the result of the explorations by the Geological Survey of China and partlythrough the expeditions sent out by other institutions, especial1y the Central INTRODUCTION Since the publication of Dr. JG Andersson’s important “” Essays on the Cenozoic of Northern China "in 1923 much material has accumulated, partly as the result of the explorations by the Geological Survey of China and partly through the expeditions sent out by other institutions, especial1y the Central