INSECTS AND ALLIED FORMS OF LIFE 



The eggs soon hatch with the warmth of the air and 

 sun, and tiny caterpillars appear. At first they are 

 so small it is with difficulty they can be distinguished 

 from the eggs. However, they soon wake up and 

 begin devouring the leaves and tender shoots of the 

 plant on which their parent has glued her eggs. Eggs 

 are not laid on plants at random. The parent knows 

 instinctively the species of plant her children will 

 thrive upon. In this selection she never makes a 

 mistake. The caterpillars feed heartily and grow 

 rapidly. The skin does not grow with the body, as 

 is the case with animals and birds ; it has to be shed 

 at frequent intervals. The old skin splits open at 

 the back of the head, and the caterpillar draws its body 

 through the rent. The most difficult part of the 

 process has yet to come. The caterpillar casts out the 

 lining of the food canal within its body. In fact, it 

 moults its skin inside and out. After this exhausting 

 effort it rests awhile to regain its old vigour and to 

 allow its jaws to harden. Then it again attacks the 

 vegetation, and eats voraciously until the next moulting 

 time. A caterpillar's life is made up of eating and 

 casting its skin. It moults from five to ten times, 

 according to the length of time it remains a caterpillar. 

 Some change into chrysalides in a month, while others 

 take longer. The caterpillar of the goat moth, for 

 instance, does not change into a chrysalis for three 

 years, and during its life it has made itself 72,000 

 times as heavy as when it emerged from the egg. 

 The privet moth caterpillar changes into a chrysalis 

 in twenty-two days, and during that short time its 



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