136 THE BIOLOGY OF THE ANIMAL 



body ? "What does the worm do with the earth 

 while digging? Compare the worm's method of 

 burrowing with that of the ant. How do they 

 differ? Examine, if possible, different kinds of 

 soil, e. g., clay, sand, loam, etc., in a garden, the 

 street, or woods, to see which kind the worm 

 inhabits, judging from the number of worms or 

 of burrows found. When a decision on this point 

 is reached, examine the soil to see if it possesses 

 any prominent chai"acters by which it is espe- 

 cially adapted for the habitation of animals Uv- 

 ing as the earthworm does. Compare the soil 

 with that inhabited by ants. 



h. Feeding. — Put some dead leaves (which must be kept 

 moist) on the surface of the earth in the flower- 

 pots in which the worms are kept. Notice after 

 a day or so, usually in the morning, that some of 

 the leaves will be found with their stems or tips 

 drawn tightly into the mouths of some of the 

 burrows in such a way as fairly to plug the en- 

 trance. Pull out one of the stalks, and note that 

 its lower end is softened and partly decayed, and 

 that it presents a frayed appearance, nearly all of 

 the soft tissues having been removed and only 

 the fibres left. Watch the flower-pot at night in 

 a quiet room, having previously laid some dead 

 leaves, scraps of cabbage-leaf, etc., on the surface 

 of the soil, and try to see hoAv the worm pulls 

 these into its burrow. Gently pinch between the 

 fingers the anterior four or five segments of a live 

 earthworm and note how the pharynx is everted, 

 thus forming a protrusible proboscis by means of 

 which the worm can seize hold of things. 



