Redfield: I remember when I was a student, Professor Raymond showed 



us a large slab of sandstone with a curious trail. They were 

 sort of moonlike depressions forming a string of beads and he 

 told us that this was a complete mystery to the paleontologists. 

 Shortly after that I went down to the sand hills. It had been 

 pretty wet and there was a shallow pool among the sand hills 

 and here was almost the identical track somewhat reduced in 

 size. I followed it across the bottom of this pool and on the lee 

 side there was a large log. Apparently it had been going across 

 on the waves and every time it hit a wave it made a little foot- 

 print. I think you will admit that this is a difficult subject. 



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