CHAPTER XVII. 



MOLLUSCS, CRUSTACEANS, AND ANNELIDA 

 (EARTH-WORMS). 



WE cannot roam about the banks of rivers or ponds 

 without constantly coming in contact with certain animals 

 commonly called slugs and snails, the first being without 

 covering, and the second forming its own habitation in the 

 shape of a shell. They both belong to the Gasteropodous 

 Mollusca. The slugs, family Limacidce, are closely allied 

 to the Helicidce, but have no external shell ; those usually 

 met with are 



The GREY SLUG (Limax agrestis), Fig. I, of a white 

 ash-colour. 



The GREAT GREY SLUG (Ltmar maximus), the largest of 

 our British species. 



The BLACK SLUG (Limax ater), Figs. 2, 3, commonly 

 known as the Black Snail, is mentioned by Izaak Walton 

 as a bait for chub, " with his belly slit to show the 

 white." Fig. 3 shows the same at rest. 



The RED SLUG (Agrion agrestis). This mollusc is by 

 some supposed to be carnivorous. It is very fond of 

 certain fungi and decayed vegetable matter. 



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