Fig. 2 — Wind ripple. - mark profiles (*/.) 
A From beach at P*-Coi borne, Ont ■ 
B From cast shown in photograph pi. 2, A. 
Geological Survey, Canada . 
Fig. 3 — Asymmetrical current ripple-mark profiles^ /.except G) 
C, From cast of ripple -mark on muddy sand shown pi. /O, B- Arrow indicates relation 
of this and succeeding profiles to current. 
D, F,f,G. Profiles resulting from tide/, currents showing amplitude varying from 3 inches 
to 4 feet . £ from cast shown in p/, 9, B. G. from cast shown in pi. 8, A. 
