Footprints 191 



by its body rather than the extremities, and 

 a curious dent in the river-shore's smooth 

 surface it was ; but before taking again to the 

 woods it walked in its peculiar way, and the 

 little footprints were quite distindt and un- 

 mistakably those of a small mammal. Had 

 the two sets of markings been preserved in 

 a slab of sandstone, no ichnologist would 

 have recognized the truth, but probably would 

 have said, " Here is a case where some leap- 

 ing creature has overtaken a small rodent and 

 devoured it." 



Difficult as fossil footprints may be to de- 

 cipher, they call up with wonderful distinft- 

 ness the long ago of other geologic ages. It 

 is hard to realize that the stone of which our 

 houses are built once formed the tide-washed 

 shore of a primeval river or the bed of a lake 

 or ocean gone long before man came upon 

 the scene. 



But, the footprints of to-day concern me 

 more. Looking over the side of the boat, I 

 saw several mussels moving slowly along and 

 making a deep, crooked groove in the ripple- 

 marked sand, " streaking the ground with 

 sinuous trace," as Milton puts it ; and the 

 school of blunt-headed minnows made little 



