103 
Museum Bulletin No. 25. 
Plate XXIV. 
A. Symmetrical ripple-mark cut by joints in Cretaceous sandstone, Ed- 
monton formation, Red Deer river, Alberta. Photograph by Geo. 
Sternberg. (Pages 43, 52.) 
B. View of shale series in which ripple-mark shown in A occurs; the man is 
standing on the ripple-mark bed; thin seams of coal occur just under 
the arrows; Edmonton formation; Red Deer river, Alberta. Photo- 
graph by Geo. Sternberg. (Page 52.) 
