Note 4 — Chapter XXVII · CAMBRIAN AND LAURENTIAN GROUPS.
Reading edition
British Association Report 1865, 1866, 1868 and Quart. Geol. Journ., vols. xxi, xxv.
Reading edition
British Association Report 1865, 1866, 1868 and Quart. Geol. Journ., vols. xxi, xxv.