330 



Shell Life 



tlie eartliworm. It is covered l)y a tough smooth 

 skin of yellow-brown, with a slight farrow along 

 each side from the neck to the shell. The foot 

 projects a little along each side. The mouth is not 

 furnished with jaws as in those mollusks that subsist 

 on vc (fetation, but its radula is covered with Xow^ 

 sickle-shaped teeth which can make an impression on 

 the skin of the human hand. Lacking jaws, the car- 

 nivorous Slug would appear at first sight to be placed 



-f,^-^^Z 



Shell-bearing Slug, TcstaceUa Iw.Uotidca (nat. size) 



at great disadvantage in securing such active iprey as 

 the wriggling earthworm ; but it does so by rapidly 

 extruding its pharynx, and transfixing its victim 

 with some of the lono^ teeth of the radula, these 

 organs being then withdrawn and the worm gradually 

 swallowed. 



The average gardener objects to the presence of 

 worms in his garden, making his lawn unsightly by 

 tlieir casts, and disturbing the soil in his seed-plots ; 

 tliereforo it might be expected he would encourage 



