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SOME INSECTS OF ECONOMIC IMPORTANCE. 



are extraordinarily abundant. The eggs, which are laid iu 

 late summer and autumn, are deposited on the ground or 

 upon grass close to it. The females may be seen engaged 

 in the operation, when they seem to progress on their hind 

 legs and tail, vibrating their wings meanwhile. With 

 their long slender bodies and legs they appear to make 

 rapid progress amongst long grasses and to get quite close 

 to the ground with their abdomen. They probably lay 

 a few eggs here and there as they move along. 



The larvae which hatch from these in about a fortnight 

 pass the winter in the soil, and in the spring and early 



Fig. 167. Crane Fly (Tipula) and larva ("leather-jacket"), slightly less than 

 natural size. 



summer feed upon the grass or corn crops chiefly, but 

 they attack all sorts of vegetable substances. They are 

 sometimes present in enormous numbers and prove extra- 

 ordinarily destructive to cereals. They are known under 

 the names of " leather- jacket," " grub," " tory worm," and 

 possibly others (see Fig. 167). 



When fully grown this larva, which structurally is a 

 maggot, is about an inch in length, blunt at both ends, 

 greyish brown in colour with two pale lines along its body. 

 There are no legs nor true head. When it enters the 

 pupal stage, curved horn-like parts appear on the head, 

 and small spines on the body. By means of these last the 



