THE POND AT LOW TIDE 



nute animalculae or refuse matter from 

 the surface of the mud, for his stomach's 

 sake. 



It is a rather interesting thing to 

 stand by and watch a Unio margariti- 

 fera daintily putting away his own par- 

 ticular brand of little necks and mock 

 turtle. At the least untoward sign of 

 interest in the affair, however, he shuts 

 up like a clam, and you will need your 

 pocket-knife if you wish to see more of 

 him. 



Where the water is only an inch deep 

 or so over the soft ooze of the bottom 

 you will see where the unio has used 

 this so-called foot as a foot should be 

 used, for he not only stands on it, but 

 walks with its help. These signs are 

 curiously erratic marks drawn as with a 

 sharpened stick for a distance sometimes 

 of yards. If you will inspect the sea- 

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