Note 78 — J. E. MARR, M.A., F.R.S. (continued 3)
Reading edition
The importance of the graptolites as indices of the geological age will be seen by perusal of Prof. Lapworth's paper "On the Geological Distribution of the Rhabdophora," Ann. and Mag. Nat. Hist., Ser. 5, vol. III. (1897).