Ill 
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Plate XXIII. A. Interference ripple-mark in a shallow pond, Hamil- 
ton county, Ind 101 
B. In terference ripple-mark, Britannia, Ont 101 
C. Plaster cast of interference ripple-mark, Britannia, 
Ont 101 
XXIV. A. Symmetrical ripple-mark, Edmonton formation, 
Red Deer river, Alberta 103 
B. View of shale series in which ripple-mark shown 
in A occurs 103 
XXV, A. Symmetrical ripple-mark on Cambrian sandstone, 
Hammond, N. Y 105 
B. Symmetrical ripple-mark, Coal Measure, Joggins, 
N.S 105 
XXVI. Symmetrical ripple-mark, Berea sandstone, Berea, Ohio 107 
XXVII. A. Asymmetrical ripple-mark on Cambrian sand- 
stone, South March, Ont 109 
B. Asymmetrical ripple-mark on quartzite, Tiger 
peak, Cour D'Alene district, Idaho 109 
XXVIII. A. Asymmetrical ripple-mark, Blacksmith canyon, 
Logan, Utah Ill 
B. Asymmetrical ripple-mark with transverse ripple- 
mark on Cambrian sandstone, Castle mountain, B.C. Ill 
XXIX. Asymmetrical ripple-mark crossed by miniature 
ripple-mark, Red beds, Soshone reservation, U.S.A. . 113 
XXX. A. Interference ripple- mark on Coal Measure sand- 
stone, Cape Breton, N.S. 115 
B. Interference ripple-mark on Berea sandstone, Ely- 
ria, Ohio 115 
XXXI. A. Current mark on Carboniferous sandstone, Joggins 
section, N. S 117 
B. Current mark on Carboniferous sandstone, Jog- 
gins section, N. S 117 
XXXII. A. Symmetrical ripple-mark with transverse ripples, 
on Carboniferous sandstone, Joggins section, N.S. , 119 
B. Symmetrical ripple-mark with saucer-shaped depres- 
sions, Carboniferous sandstone, Joggins section, N.S. 1 19 
XXXIII. Current mark on Carboniferous sandstone, Joggins 
section, N. S 121 
Figure 1. Wind ripple-mark, profile after Lyell 9 
2. Wind ripple-mark profiles. 9 
3. Asymmetrical current, ripple-mark profiles 9 
4. Symmetrical, wave, ripple-mark profile 23 
5. Entrance to Squam estuary, Mass 33 
6. Current mark profiles 43 
7. Ripple- mark profiles on sandstone 43 
