Note 15 — J. E. MARR, M.A., F.R.S. (continued 2)

The chronological words have been used so loosely that it is doubtful whether any good will come of trying to restrict their use, and Sir A. Geikie has pointed out the confusion which would arise if the term group be employed for the largest divisions (Palæozoic, &c.). The terms System, Series and Stage may well be employed in the senses suggested by the Congress.