28 "^^ HABITS OF WOEMS. Chap. L 



piano ; and their sensitiveness to jars varied 

 much at different times. It has often been 

 said that if the ground is beaten or otherwise 

 made to tremble, worms believe that they 

 are pursued by a mole and leave their 

 burrows. I beat the ground in many places 

 where worms abounded, but not one emerged. 

 When, however, the ground is dug with a 

 fork and is violently disturbed beneath a 

 worm, it will often crawl quickly out of its 

 burrow. 



The whole body of a worm is sensitive to 

 contact. A slight puff of air from the mouth 

 causes an instant retreat. The glass plates 

 placed over the pots did not fit closely, and 

 blowing through the very narrow chinks thus 

 left, often sufficed to cause a rapid retreat. 

 They sometimes perceived the eddies in the 

 air caused by quickly removing the glass 

 plates. When a worm first comes out of its 

 burrow, it generally moves the much ex- 

 tended anterior extremity of its body from 

 side to side in all directions, apparently as an 

 organ of touch ; and there is some reason to 

 believe, as we shall see in the next chapter, 

 that they are thus enabled to gain a general 



