INSECTS AND VERMES 435 



the ends of which they often draw into their holes ; even 

 in copulation their hinder parts never quit their holes ; 

 so that no two, except they lie within reach of each 

 other's bodies, can have any commerce of that kind ; but 

 as every individual is an hermaphrodite, there is no 

 difficulty in meeting with a mate, as would be the case 

 were they of different sexes. 



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 (pepeotKo^^ does not come forth at all till about 

 April loth, 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 inclemencies. 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 ground. Hence the way to be rid of them 

 is to kill as many as possible before they begin to breed. 



Large, grey, shell-less cellar snails lay themselves up 

 about the same time with those that live abroad ; hence it 

 is plain that a defect of warmth is not the only cause that 

 influences their retreat. 



SNAKES SLOUGH 



"There the snake throws her enamelled skin." 



Shakspeare, Mids.-Night's Dream. 



About the middle of this month (September) we found 

 in a field near a hedge the slough of a large snake, which 



