CHAPTER XIV 



THE ENEMIES OF INSECTS 



Probably the most baneful enemies of insects are found 

 among their own kith and kin, for the number of pre- 

 daceous species and parasites is very great. But when we 

 realise that something like four-fifths of all existing land 

 animals are insects, we are not surprised to learn that 

 they are assailed by many creatures other than members 

 of their own class. Whole groups of animals, from 

 mammals downward, find in insects their chief— often 

 their only — source of food. In Britain, the mole, the 

 shrews, and the hedgehog depend largely upon an insect 

 dietary, the mole doing good service to agriculturists by 

 destroying immense numbers of grubs and caterpillars 

 which harbour in the soil; while our native bats war 

 against nocturnal insects, which they capture on the wing. 

 Abroad, we find many mammals whose structure and 

 habits are profoundly modified to fit them for an in- 

 sectivorous career. For instance, the great ant-eater of 

 South America is toothless, and has a long, mobile tongue 

 which is kept constantly sticky by the secretions of large 

 salivary glands. With this organ it sweeps up ants and 

 other insects after breaking into their habitations by means 

 of its powerful claws. 



Lizards feed largely upon insects. Most of them are 

 extremely agile and hunt their prey. But the interesting 

 chameleons lurk motionless among the branches of trees 

 and shrubs, and dart out their long, sticky tongues to 

 seize such insects as may chance to settle within reach. 



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