Insect Friends 



four well-marked stages — egg, active larva, pupa, 

 and perfect insect. In the second and fourth the 

 food of ladybirds consists of greenflies and scale 

 insects. Where ladybirds are abundant greenflies 

 rarely do very serious harm. The larvae are slate- 

 coloured with black spots, the pupae are found on 

 the foKage, and can hardly be mistaken for anjrthing 

 else if larvae and ladybird are known ; the yellow 

 eggs standing on end are conspicuous on the leaves 

 in spring and summer ; the winter is passed in the 

 perfect stage. 



The larvae of the laoewing fly also devour green- 

 flies. The curious eggs fixed to leaves by trans- 

 parent threads a quarter of an inch long are well 

 known objects which often excite curiosity. The 

 flies themselves with green bodies, golden eyes, 

 and large gauzy wings also attract attention, while 

 the repulsive odour they exude when touched render 

 them almost immune from destruction. 



Hover flies are well known to all from their habit 

 of hovering over flowers. Most of them feed on 

 pollen, but their rather slug-like brown or green 

 larvae feed, as a rule, on greenflies. 



Earwigs, ants, and wasps devour many insects, 

 but their good services on this side have to be 

 balanced against damage done to plants or fruits 

 on the other. The sohtary wasps are, , however, 

 wholly friendly in their habits, and their nests in 

 hollow sticks and the hke should be preserved — 



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