CHAP. V.] DESTROYING INSECTS. 113 



thrips, the red spider or rather mite (Acarna 

 telarius), various kinds of Tipula or gaffer long- 

 legs, wood-lice, and earth-worms, are all found 

 on plants, and are all more or less injurious to 

 them. In the general destruction of insects the 

 lady-bird should always be spared, as, both in 

 its larva and its perfect state, it lives on the 

 larvae of the green fly or aphis. 



Snails and Slugs are more destructive to 

 vegetation than any kind of insect; and they 

 are still more difficult to get rid of. There is 

 a very small grey slug-, that is peculiarly inju- 

 rious to plants in pots ; the large grey slug is 

 also very destructive, and the common garden 

 snail. The beautifully banded snail (Helix ne- 

 moralis) is, however, supposed to live partly on 

 earth-worms, and the shell slug (Testacella 

 scutella) lives entirely on them. The usual 

 modes of entrapping snails, slugs, and wood- 

 lice, are, laying down slices of raw potatoes or 

 cabbage leaves at night, and examining them 

 before the dew is oft the plants in the morning. 

 As, however, this requires very early rising, a 

 more convenient method is to lay a few flower- 

 pots upon their side.-, near the places where the 

 snails have committed their ravages ; and the 

 snails, which can neither move nor feed unless 

 the ground be wet with dew or rain, will gene- 

 rally be found to take refuge in the flower-pots 

 from the heat of the sun. They are likewise 

 often found, in the middle of the day, sticking 

 against walls under ivy, or in box edgings. In 

 gardens very much infested with snails, search 

 should be made in winter among all the ivy and 

 box in the garden; and all the snails found in a 



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