Note 28 — J. E. MARR, M.A., F.R.S. (continued 2)
Reading edition
Harker, Alfred, "The Bala Volcanic Series of Caernarvonshire" (Sedgwick Essay for 1888), Fig. 5.
Reading edition
Harker, Alfred, "The Bala Volcanic Series of Caernarvonshire" (Sedgwick Essay for 1888), Fig. 5.