- GeoRef, Copyright 2004, American Geological Institute. Reference includes data from Bibliography and Index of Geology Exclusive of North America, Geological Society of America, Boulder, CO, United States
A discussion and appreciation of a paper by C. H. Holland (see preceding abstract). It is suggested that an unresolved problem still exists in the naming of the beds above the British Ludlovian stage which are now brought within the Silurian. It is proposed that the Ludlovian be extended to include the beds in question.