42 INJURIOUS AND USEFUL INSECTS 



How can this pest be got under? is the first and usually 

 the only question that the farmer puts when he sees a horde 

 of insects devouring his crop. It is 

 easy to mention remedies which are 

 promising and worth trying; it is 

 usually hard to mention one which is 

 CD certain, rapid, and cheap. In the case 



Fig. 33.— Larva and egg of of the flea-beetle the best remedies 

 cTtis-^Fa^lnseas ■■'''''''" bitherto proposed seem to be:— (i) 

 Clean farming. Get rid of weeds, and 

 especially of Cruciferous weeds, from the borders of the 

 fields. (2) Good feeding. Help the crop over the stage 

 of attack by manuring and watering. (3) Poison- 

 ing the pest. This is no easy matter. It is 

 hard to wet the beetles or the leaves with any 

 poisonous solution, and impossible to reach 

 the larva inside the leaf, or the pupte under- 

 ground. Soft soap and paraffin worked up in 

 water and applied with a Strawsoniser seems 

 a likely thing to try. Dressings of two parts 

 of lime to one of soot have proved useful 

 where the beetles abound. In America solu- 

 tions of Paris green or some other arsenical f^'^„f'^-'~-''f,"P'' 

 compound are used freely in such cases, but magnified. From 

 the English farmer as yet shrinks from the fi,"/ecL" " ''''™ 

 risk of using large quantities of a poison 

 which might destroy other life than that of insects (see 

 Part IV.). 



9. LADY-BIEDS {Coccinellidae) 



There are hardly any insects more familiar than these. 

 Every child who plays in a garden knows the bright-coloured 

 dumpy body of the lady-bird, and has seen it fly, crumpling 

 up its large and gauzy wings beneath the hard, shiny wing- 

 covers, when it alights again. But it is only with some 

 trouble that all the stages of the life-history are discovered. 

 The eggs are yellow, and laid in clusters upon plants infested 

 by aphids or plant-lice. It is upon the aphids that the 

 larvae and full-grown beetles subsist, and they are born where 



