INSECTS AND ALLIED FORMS OF LIFE 



alis. By this time the grubs have also become adult 

 and changed into chrysalides, and at the proper time, 

 instead of a beautiful moth or butterfly issuing from 

 the caterpillar chrysalis, a number of ichneumon flies 

 emerge. They fly away, mate, and the females seek 

 out fresh caterpillar victims. 



Caterpillars evolve various schemes to protect 

 themselves against their bird enemies. They feed 

 on the under sides of leaves, hide by day and issue 

 forth by night ; bore into trees, manufacture a nasty 

 secretion which makes birds sick, and grow stiff hairs 

 on their bodies ; others imitate dry twigs, pretend to 

 be dead, or frighten their enemies by assuming 

 alarming attitudes. 



Birds have their likes and dislikes. Some birde 

 feed on certain species of caterpillars which other 

 kinds of birds will not touch. For instance, the 

 cuckoos feed very largely on hairy caterpillars which 

 the majority of other birds will not eat. 



Sometimes caterpillars multiply so alarmingly that 

 they swarm in uncountable multitudes and strip 

 forest, veld, and farms bare, leaving famine in their 

 wake. In 19 19 the army moth caterpillar stripped 

 the veld as bare as a road over wide stretches of country 

 in South Africa. The army moth flies by night, and 

 night jars and insectivorous bats are their chief 

 enemies ; yet little or nothing is done to protect these 

 night-flying birds and mammals. 



Most species of moths die after one, or at most 

 two, batches of eggs have been laid ; but some kinds 

 hibernate during the winter. Eggs and chrysalides 



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