PLANT LICE 



the winter eggs. The eggs are again collected by the ants 

 and carried to safety for the winter into the depths of their 

 underground abodes. All this the ants do for the aphids 

 in exchange for the honey dew they receive from them. 

 The ants have so domesticated these corn-root aphids 

 that the aphids would perish without their care. The 

 farmer, therefore, who would rid his cornfield of the aphid 

 pest, proceeds with extermination measures against the 

 ants. 



The crowded aphid colonies exposed on stems and 

 leaves naturally form the happy hunting grounds for a 



B 



Fig. 102. A common ladybird beetle, Coccinella navemnotata, that 



feeds on aphids. (Enlarged 5 times) 



A, the larva. B, the adult beetle 



host of predacious insects. Here are thousands of soft- 

 bodied creatures, all herded together, and each tethered 

 to one spot bv the bristles of its beak thrust deep into the 

 tissues of the plant — a pot-hunter's paradise, truly. 

 Consequently, the placid lives of the aphids have many 

 interruptions, and vast numbers of the succulent creatures 

 serve only as half-way stages in the food cycle of some 

 other insect. The aphids have small powers of active 



•73 



