Title: Controversy in Victorian geology
Subjects: Geology, Silurian, Wales, Cambrian, Stratigraphic Geology, History, Geology, stratigraphic, cambrian, Geology, stratigraphic, silurian, Stratigraphie, Histoire, Géologie, Cambrian Geologic Period, Silurian Geologic Period, Geologie, Cambrium, Siluur, Controversen, Kambrium-Silur-Kontroverse, Cambrien, Silurien
Places: Wales
Time periods: Cambrian, Silurian