INSECTS AND VERMES. 281 



SNAILS AND SLUGS. 



The shell-less snails called slugs are in 

 motion all the Winter in mild weather, 

 and commit great depredations on garden 

 plants, and much injure the green wheat, 

 the loss of which is imputed to earth- 

 worms ; while the shelled snail, the (peptoiy.o;, 

 does not come forth at all till about April 

 10th, and not only lays itself up pretty 

 early in Autumn, in places secure from 

 frost, but also throws out round the mouth 

 of its shell a thick operculum formed from 

 its own saliva; so that it is perfectly secured, 

 and corked up as it were, from all incle 

 mencies. The cause why the slugs are 

 able to endure the cold so much better * 

 than shell-snails is, that their bodies are 

 covered with slime as whales are with 

 blubber. 



Snails copulate about Midsummer ; and 

 soon after deposit their eggs in the mould 

 by running their heads and bodies under 



