A.QSl 
8.(32 . 9 
C. (33) 
D. (27) 
EM 
F.(t6) 
G. (8) 
H. (9) 
Geological Survey, Ca.na.da. 
Fig. 4— Symmetrical wave ripple - mark profiles (xt.) 
AB,C,D. From lake bottom ripple -mark formed in water ‘finches to 
12 inches deep. £ and F from water 6 feet deep . 
G. From wave fbrmed ripple - mark slightly modified by & weak current 
in 5 inches of water , S*' Lawrence River. 
H. From rippie -mark formed under 6 inches of water on S$ Lawrence 
river bottom by wave and current influence combined resulting in 
sisymme tricaJ crests. 
