WORMS. 



411 



in the sand ; others form themselves a sort of tube or habitation 

 of sand, bits of dirt, gravel, or other materials ; and others exude 

 from their surfaces a calcareous matter, which produces a sheli 

 around them. 



Among the animals belonging to this class are the earth- 

 worm, the leech, and the hair-worm. 



Earth-worms are familiar to all. They attain sometimes 

 to the length of a foot, and have as many as a hundred and 



■si^SS^- 



Earth-wormB. 



twenty rings, each of which is furnished with the little bristles or 

 spines above mentioned. They emit through certain pores a slimy 

 fluid, which lubricates their bodies, and thus gives them an easier 

 passage through the earth, which they traverse in every direction. 

 They feed upon roots, woody fibres, and the remains of animal 

 and vegetable matter. They swallow earth also in considerable- 



