CHAPTER XXIX 



SLUGS LAND AND POND SNAILS COLLECTIONS OF SHELLS 



SLUGS 



THE snail which was considered in Lesson XXVII is so different from 

 the majority of creatures ordinarily met with that it has an attraction 

 for many, and its hard shell enables it to be handled without 

 necessarily touching its moist body. Less attractive, though by no 

 means less interesting, are the slugs. With few exceptions they have 



FIGURE 206. The great Grey Slug. 



lost, in course of time, the outside shell seen in the snail, but many 

 have an internal shelly plate which is not developed in the latter. 

 Apart from the changes in colour which many slugs seem to undergo 

 during their lifetime, and with regard to which little work has been 

 done, one of their most interesting features is their power of finding 

 their way back to the spot which they have chosen as their home, 

 after their nightly excursion, a fact which can be proved by an examina- 



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