290 WAVES OF SAND AND SNOW 



current were producing the small ripples at the 

 same time that the large waves were being formed 

 by the general drift. I find, however, on re- 

 examination of my photographs that the current - 

 marks occur close to the lee of the cliff of the 

 large sand-waves, and that even here they face 

 with the direct current. But if they were formed 

 while the eddy was active they would, I suppose, 

 face towards the cliff — i.e., in the direction of the 

 return current. The current-mark left on the dried- 

 out sand-waves may therefore only be what is 

 formed during the subsidence of the water when 

 the depth is insufficient for the growth of the larger 

 sand-waves, and when they are, on the contrary, 

 being flattened out. If so, the sand-waves may 

 perhaps have an unrippled surface during their 

 growth. Further observations are required on this 

 point, to which my attention was called by Dr. 

 J. C. Owens. 



