SAND DUNES AND SALT MARSHES 



Another little crustacean that I will call the 

 beach sow-bug, as it lacks a common name, 

 is flattened from above downwards instead of 

 from side to side, like the beach flea, and 

 makes interesting wandering marks between 

 tides, for instead of hopping like its nimble 

 cousin it progresses very slowly below the 

 surface. Similar marks are made by peri- 

 winkles and other small mollusks, while the 

 clam-worm writes its name in the same way 

 but more plainly. 



The clam-worm is worthy of more than 

 passing notice, for, if one looks fairly at it, 

 it is not a disgustmg beast but one of con- 

 siderable beauty. Indeed it is called scien- 

 tifically a sea nymph. It is often a foot or 

 more in length, of a bluish green color and 

 somewhat iridescent, and it is provided on 

 each side of its flattened body with innumer- 

 able bristle-bearing legs. It is a voracious 

 creature, and comes out of its burrow in the 

 sand or mud to feed on other worms and on 

 small shrimps and snails, which it captures 

 with a pair of horny notched jaws that are 

 kept concealed in its gullet until needed. 



While on the subject of worms, I must men- 

 tion the sea-mouse, an extraordinary worm 



256 



